Cadillac P0300 Engine Misfire

When car is at a red light or stopped but in gear it feels like it will kill at any minute. We have changed coils, plugs, oil filter. ENGINE MISFIRE CODES P0300 - Multiple Cylinder Misfire P0301 - Cylinder 1 Misfire P0302 - Cylinder 2 Misfire P0303 - Cylinder 3 Misfire P0304 - Cylinder 4 Misfire P0305 - Cylinder 5 Misfire P0306 - Cylinder 6 Misfire include--Purchase date -mileage at which it threw the first code,and any recurring (what code)-your request to dealer and drop. Call Us: +1 (714) 249-4800 Text Us: +1 (415) 849-4800 Text Us: +1 (415) 849-4800. Hello, I have a Lincoln LS 2001 V8 and I had the engine serviced some months ago for a misfire in the engine. If that increase and/or decrease is more than 2 percent, the Powertrain Control Module will store the P0300 trouble code. I am getting several codes, p0300, p0301, p0303, and p0304. The engine light started flashing whenever the speed exceeded 20 mph. All the work with covered under warranty. It’s a pretty common problem for LS based truck motors to develop a P0300 problem when no misfire exists. When the startup ECT is colder than -7°C (+19°F), this diagnostic will be delayed until the ECT is warmer than. Circuit Description. SOURCE: cylinder 6 misfire for 2000 cadillac deville 4. The code I don't recall. 25 V when the EGR valve is closed. Misfires Lean Negative Fuel Trims Help. What Does Code P0300 Mean? OBD II fault code P0300 is a generic code that is defined as " Random/Multiple Cylinder Misfire Detected", and is set when the PCM (Powertrain Control Module) detects either randomly misfiring cylinders, or misfires on multiple cylinders. Swung by AAP to read the code and got a P0300 code, random misfire - replace timing chain. I too had to replace an engine at 145,000 miles. Possible Causes: Fuel injectors, related wiring, sensors and computer issues Running out of gas, or poor fuel quality. Cadillac CTS Forums 2003-2019. It's a 2004 cadillac cts with the 3. P0301 – Misfire on cylinder #1. Code P0300 stands for "Random or Multiple Cylinder Misfire Detected. I am still getting a P0300 code (multilple engine misfire) and the check engine light blinks only when the car is moving. OBD2 Code P0300 Cadillac definition: Basically this means that the the car’s computer has detected that not all of the engine’s cylinders are firing properly. I recently installed NGK Tr7ix plugs and MSD wires. 6 L 302 hp Gas Another common cause would be a fuel delivery issue causing the engine to misfire causing a P0300 code (or any misfire related code) to be stored in the computer. P0301 through P0304 indicate misfires pertaining to individual cylinders, i. Shop 2016 Buick LaCrosse vehicles for sale in Independence, KS at Cars. I removed a spark plug wire and an injector clip in order to make the engine misfire and cause a P0300 code in the computer. After doing some research I found out what the codes meant (random misfire) so I changed the spark plugs and basically everything that was within my ability. But once you take away whats not wrong with the car the majority of the time the problem ends up being decently simple to repair. P0300 2006 NISSAN MAXIMA Description When a misfire occurs, engine speed will fluctuate. His And Her Money 389,878 views. Trouble Codes › P0300. 0L P0300 random misfire Jul 25 2017, 1:29am 2007 Silverado 2500HD Classic, 182,000 miles, 6. p0301 p0302 p0303 p0304 p0305 p0306, Chevy P0300 P0304 Chevy Colorado Silverado GMC vehicles - Ignition Coil Detected. All the work with covered under warranty. engine runs fine cold. The engine coolant temperature (ECT) is between -7 and +130°C (+19 and +266°F). Preventive engine cleaning enables you to restore engine parts rather than replacing them, thereby saving vehicle owners on costly parts, such as a new turbocharger ($ 1. I had experienced a slightly rough idle previously (nothing serious) and had been unable to track it down. Cadillac DeVille 1985 to 2005 including:1985-1992. If the situation worsens, the engine bucks more often and the performance drops significantly. P0300 code random misfire This is a discussion on P0300 code random misfire within the General Help forums, part of the LSx Technical Help Section category; I'm talking about the two big bulk head connectors that run into the ECM @ the passengers side of the. 0 Gen III V8 Engines and Misfires on One Bank - kw CEL diagnostics driveability DTC P0171 P0172 P0174 P0175 P0300 P0301 P0302 P0303 P0304 P0305 P0306 P0307 P0308 #PIP3056 - (Jul 12, 2004) 97 - 05 Vehicles with 4. It ran erratic 2 days later, and then I checked the engine codes with an OBD. Javier S · Registered. Having the misfire code P0300 for the last month just took it to the dealership this morning and it turns out the fix was a software update. Jump to Latest Follow (car was still warm) and the engine began to misfire and vibrate causing a very rough idle and the engine to shut-off after about 5 seconds. I have changed out the distributor, spark plugs, wires, pcv valve, fuel filter, o2 sensor, had valves re-adjusted, new valve cover gasket, Compression test was done and had the injectors checked for pulse. Stored Fault Codes: P0300-RANDOM MULTIPLE CYLINDER MISFIRE,P0303-CYLINDER 3 MISFIRE,P0203-INJECTOR CIRCUIT 3,P0204-INJECTOR CIRCUIT 4. One problem is vacuum leaks in the intake tubing or hoses attached to the intake manifold. Just went through code P0300 on an 2010 chrysler town and country van 4. Top of Form. All of these issues can cause a flashing check engine light. Reset check-engine light and a few minutes later got P0003, P0300, P0302, P0303, & C0300. Now, there a misfire dealing with, I believe, another cylinder. White smoke and/or coolant odor may come from exhaust for an extended period of time at cold start as well. A misfire occurs when an insufficient amount of fuel is burning in a cylinder. picks up a miss at Wide open throttle, then immediately drops those inj drivers until key is cycled. This vehicle's codes were P0300, P0352, P0354, P0356 and P0358 it could have just as easily have been codes P0300, P0351, P0353, P0355 and P0357. If the computer detects an individual cylinder is not firing properly a P0301 would set for cylinder one. I noticed the car felt really wierd and not running right and that lasted about. 6 2008 petrol model. Something is causing cylinders to misfire at random, which is a lot less cut and dry than a cylinder specific misfire code. Why You Need a Home Based Business and How to Start! with Dr. It will often be accompanied by codes P0301-P0308. I changed 5 of the 6 plugs, but it came back on. 6L with 71000 miles. Engine MIL was on. Code P0300 stands for "Random or Multiple Cylinder Misfire Detected. One problem is vacuum leaks in the intake tubing or hoses attached to the intake manifold. What sets diagnostic trouble code P0300? An internal-combustion engine needs four things to run. 4500 miles, and had the P0300 Cylinder misfire code 2 times now. Tune it up, new ac/delco plugs, good plug wires, fuel filter and don't forget to look at the cabin and air filters as well. had coil 2 and all spark plugs replaced. Re: CEL code P0300 random/multiple misfire « Reply #10 on: October 19, 2010, 09:51:18 PM » Yeah I had read about that occuring, but the cel for the most part only blinks when its past 4k rpm, but occasionally it will blink at random low rpm driving which is what makes me want to try the coils before the sensors but meh we shall see, gotta. In a modern combustion engine, if more than one cylinder misfires, this will increase or decrease the revolutions per minute (RPM) of the crankshaft. We recommend Torque Pro. If that increase and/or decrease is more than 2 percent, the Powertrain Control Module will store the P0300 trouble code. A P0300 Cadillac diagnostic code indicates a random or multiple misfire. 2009 Cadillac CTS Engine Technical Service Bulletins TSB Number: PIP5628B NHTSA Number: 10176326 communicates information that will need to be provided to tac to aid in diagnosing if a vehicle comes in with misfire and DTC codes P0300 - P0308 and/or P050D. For instance cylinder 1 misfire is P0301, cylinder 2 is P0302 etc. You will see why later in this article. Post by Fiesta2 » Mon May 18, 2015 11:12 pm. Misfire check showed heavy misfires in cylinders 1-3-5. Loss of engine power; Rough running; Out of State Cadillac dealership attempted ABS repairs / no luck. Pulled that plug and it was damp with fuel. 000), DPF ($ 600 - 2. According to the previous owner, the pre-cats were gutted before the current motor was put in the car. A misfire occurs when an insufficient amount of fuel is burning in a cylinder. 2004-2007 Cadillac CTS or SRX Engine Computer Repair Kit. It's throwing codes p0300-p0304 and p1399, in other words, its a random cylinder misfire on all cylinders. P0301 through P0312 indicate a particular cylinder misfire and will usually be accompanied by a second or third trouble code indicating specifics. 0L I've been reading for weeks on these humble forums about all the P0300 trouble codes. vehicle only misses at an idle. P0300 CHEVROLET - Cylinder Misfire Detected Random Cylinders - Auto Codes. So to recap the symptoms - Misfire occurred after cam/spring installation. P0300 is vaguer than other misfire codes and doesn't provide any insight on which one of the cylinders might have experienced the issue. bring idle up to 1200 rpm, misfires stop. The code P0201 means that the misfires are recorded by the fuel system not firing on the cylinders, meaning the fuel injectors on cylinder 1 and cylinder 2 and randomly shutting off. An engine misfire happens when one of the cylinders in your engine fails to function properly. Engine misfire, P0300: Author: Nick Hibberd | Hibtech Auto-Electrical Diagnostics: Vauxhall Astra | Misfire under load. Meaning of P0300 engine trouble code is a kind of powertrain trouble code and theoretically you can drive for a few weeks or even months with a broken MAF sensor. So I figured i just need a tune up so I went and bought new plugs and wires. It's throwing codes p0300-p0304 and p1399, in other words, its a random cylinder misfire on all cylinders. Lynn Richardson - Duration: 54:48. The Crankshaft Position sensor is mounted through the side of the engine block at the rear of Bank 2 behind the starter assembly. My car has 65k on 04' cadilac srx and runs rough. engine misfire code P0300 Saab 9-3T - intermittent rough running, smell of gas, injectors staying on 2007 9-3T fault codes: P1682, P0201, P0202, P0203, P0204 2007 this came in with a customer complaint of intermittently running How To Fix Engine Hesitation During Acceleration - Easy Fix! Trouble Code P0018 P0087 P0101 P0107. You'll likely find another OBD-II code—from P0301 to P0308—alongside P0300 as these all point to engine. The only thing that's been changed recently were the spark plugs and the right MM (within the last week). I've inspected the wiring the best I can. DTC P0300 The ECM is detecting a crankshaft speed change indicating a random misfire is occuring that exceeds mandated emission level standards or is at catalytic converter damaging levels. I narrowed it down to what I thought was spark plugs and 2 bad coils, changed them and it helped for awhile (about two miles). Categories Automotive Repair Videos, Check Engine Light, DIY Auto Repair Tags 4. P0301 - Cylinder 1 misfire. 0 liter 3ZR. Cadillac - Cts :: 2004 - Check Engine Light Flashes / Codes P0300 And P0303 Aug 23, 2012. With a few simple tools, a little thought, and these tips, most enthusiasts can cure the engine misfires. Unable to isolate cause of misfires. Having an issue with Vauxhall Zafira 1. I have a Code P0300 which is a Random Misfire Code. The misfire of the engine cylinder causes the engine speed to fluctuate. A P0300 diagnostic code on a Nissan Quest is caused by an engine misfire. A P0300 diagnostic code indicates a random or multiple misfire. DTC P0300 Engine Misfire Detected. Worse when engine warms up but idles rough even when cold. Something is causing cylinders to misfire at random, which is a lot less cut and dry than a cylinder specific misfire code. 5L EcoBoost in your shop with misfire code s P0300-0306 pull the plugs and coil boots and look for carbon tracks on the insulator of the plugs. Every cylinder ends up misfiring. Categories Automotive Repair Videos, Check Engine Light, DIY Auto Repair Tags 4. P0302 CADILLAC Meaning When a misfire occurs, engine speed will fluctuate. Javier S · Registered. 6 LGX All Cadillac ATS 2016 - 2017 All All 3. Tune it up, new ac/delco plugs, good plug wires, fuel filter and don't forget to look at the cabin and air filters as well. Since install I am getting the P0300 code. Cadillac Misses at idle,P0300,Northstar This Cadillac DTS has a misfire only at idle. 1) Engine misfire - need to replace cylinder heads 2) Front drive shaft loose - need to replace the shaft. Subject: Information on Engine Misfire MIL/SES Light Illuminated or Flashing DTC P0300, P0301, P0302, P0303, P0304, P0305, P0306, P0307, P0308, P0420 or P0430 Models: 1999-2007 Cadillac, Chevrolet, GMC Full-Size Pickup and/or Utility Trucks with 4. It keeps throwing pcm p0300 codes, engine light, and idles rough at stop signs and when parked. The engine idles very rough and you can definitely tell it's a misfire from the exhaust end. If the engine speed fluctuates enough to cause the. P0300 CADILLAC Cylinder Misfire Detected Random Cylinders. DTC P0300 Engine Misfire Detected. P0302 Cylinder #2 Misfire. P0302 – Misfire on cylinder #2. 6 LGX All Cadillac CT6 2016 - 2018 All All 3. This did nothing for me. Jump to Latest Follow 1 - 10 of 10 Posts. The engine idle quality is poor. Forums > 1991 - 1999 Tahoe & Yukon Models. A few days later check engine light came on and code p0352 came up. P0300 Diagnostic Code - Random Misfire Symptoms. surges at idle. GMC Yukon Forum | Tahoe Z71 | Cadillac Escalade - Tahoe Yukon Forum. P0301 Misfire Cylinder #1. 5/13/14 replaced camshaft sensor bank 1 exhaust 5/22/14 sel and service stabilitrak lights on with code P0300-00. -Code P0306 (Misfire #6 Cylinder)-Rough Idle-Flashing Check engine light-Service Stabilitrak/Traction Control Messages-Hard gear shift from 1-2,2-3 also on downshift-Very high oil Consumption (3 quarts low) Tried:-New plugs,wires,coils-Checked for spark-Ensured all connections were tight Need to try:-Check for vacuum leaks. Code P0300 – Engine Misfire Detected. Jump to Latest Follow 1 - 1 of 1 Posts. com database, we found four main sources of problems with Cadillac 5. 9 (1987) T9. Engine Misfire/Tick Noise, Malfunction Indicator Lamp (MIL) On, DTC P0300 Set: Models: 2015-2016 Cadillac Escalade: 2016 Cadillac CTS-V: 2014 Chevrolet Silverado 1500: 2014 - 2016 Chevrolet Corvette: 2015 - 2016 Chevrolet Silverado, Suburban, Tahoe: 2016 Chevrolet Camaro: 2014 GMC Sierra 1500: 2015 - 2016 GMC Sierra, Yukon, Yukon XL. SOURCE: cylinder 6 misfire for 2000 cadillac deville 4. P0308 indicates that cylinder number 8 is experiencing misfires. What is Code P0300? To put it simply, this code means that one of the cylinders in your vehicle misfired and that the misfire was detected and reported by your car's computer. 1) Engine misfire - need to replace cylinder heads 2) Front drive shaft loose - need to replace the shaft. All modern applications employ highly sophisticated circuits whose sole purpose is to detect misfires. I have a 2004 Cadillac deville that has the P0300 code and flashing check engine light on it was missing and sputtering. On the way to the shop for yearly inspection (can you believe it), SES light starts blinking, engine runs rough, exhaust smell. Posted at 13:44h in Blogs that need attention, P0300 random misfire and P0305 cylinder 5 misfires. Hello, I have a Lincoln LS 2001 V8 and I had the engine serviced some months ago for a misfire in the engine. For the past week or 2 had a check engine light but I didn't get a chance to scan it. Subject: Information on Engine Misfire MIL/SES Light Illuminated or Flashing DTC P0300, P0301, P0302, P0303, P0304, P0305, P0306, P0307, P0308, P0420 or P0430 Models: 1999-2007 Cadillac, Chevrolet, GMC Full-Size Pickup and/or Utility Trucks with 4. The only thing that's been changed recently were the spark plugs and the right MM (within the last week). 2001 Cadillac Seville - Powertrain - Engine Controls - 4. Possible cause: * Improper spark plug * Insufficient compression * Incorrect fuel pressure. Could be 303 also. Before explaining the cause you must first understand HOW a computer knows you have a misfire. The misfire caused my mileage to go down to like 8 mpg. Less common reasons for an engine misfire include a faulty fuel injector, an intake air leak, insufficient cylinder pressure and incorrect fuel pressure. while at an idle, engine runs rough but not like all 3. Taking your car into a shop will cost you around $200 depending on the car. I am thinking crank pos sensor? When he was driving it the stability control light also was on. 6L V6 after ~42,000mi on my Saturn Outlook. It's throwing codes p0300-p0304 and p1399, in other words, its a random cylinder misfire on all cylinders. I hooked the scanner up and saw a p0300 code. P0300 Description. This misfire triggers error code P0300. p0301 p0302 p0303 p0304 p0305 p0306, Chevy P0300 P0304 Chevy Colorado Silverado GMC vehicles - Ignition Coil Detected. I have owned it a week and a half and most of that was in the shop for the shift out of park issue. Replacing coil pack and plugs had not cured the fault. As the vehicle was out of warranty, I took it to the local parts store, read the codes (P0300 and P0303 misfire codes were present) the 2nd code localized the misfire to cylinder 3. 4l misfire P0305 P0304 P0300 P0316 P0171 After having all of my sparkplugs replaced my truck was running much worse. Replaced Plugs, Coils, Wires. com database, we found four main sources of problems with Cadillac 5. had coil 2 and all spark plugs replaced. It recently began misfiring while I was driving usually on the highway at speed and never at idle. Lynn Richardson - Duration: 54:48. acts like it is starved for gas when trying to accelorate on the road. P0300 indicates a random misfire. A misfire condition that sets a diagnostic trouble code (P0301, P0302, P0303, P0304, P0305, P0306, P0307, P0308 ) and thus illuminates the check engine light is one that is usually easy to diagnose and repair. P0300 engine misfire problem. Joined 2. Cadillac CTS First Generation Forum - 2003 - 2007. Engine misfires can be a mysterious, frustrating problem—and information around them often makes them sound worse than they are. 6l misfire, 4. When the misfire monitor detects a misfire, it will trigger the check engine light with the specific cylinder number as the last digit in the P030X code. No signal to coil/s or injector/s as a result of a faulty engine computer in your 2004-2007 Cadillac CTS or SRX?. Call Us: +1 (714) 249-4800 Text Us: +1 (415) 849-4800 Text Us: +1 (415) 849-4800. it started to run on 3 cylinders i think. Jump to Latest Follow 1 - 1 of 1 Posts. Top of Form. When the startup ECT is colder than -7°C (+19°F), this diagnostic will be delayed until the ECT is warmer than. Javier S · Registered. White smoke and/or coolant odor may come from exhaust for an extended period of time at cold start as well. Related Posts: Spark Plug Stripped In Ford F-150 Cylinder Head; 2004 Chevy Impala 3. 5-liter four-cylinder base engine. I have a 2007 Chrysler 300 touring. Checking the codes, I had multiple misfires (P0300) and misfires on cylinders 2, 3, 5 (P0302, P0303, P0305). Categories Automotive Repair Videos, Check Engine Light, DIY Auto Repair Tags 4. ECU has been tested and passed test. not the answer your looking forthis is for 2009's but may give some insight Repeat Catalytic Converter Failure January 4, 2010 5:51 PM On some 2009 Enclave, Traverse, Acadia and OUTLOOK models, the ignition coil circuit connections may cause engine misfires that may lead to repeat catalytic converter failure as well as scoring of the cylinder bores. I switched the coils between cylinders 2 and 4 to rule out a bad coil. If the engine speed fluctuates enough to cause the Crankshaft Position (CKP) sensor signal to vary, the Engine Control Module (ECM) can determine that a misfire is occurring. No such luck just the same P0300 random misfire code. My 2000 CRV started running rough very suddenly a few days ago. Follow the Repair. During this condition, the ECM monitors the CKP sensor signal every 1,000 engine revolutions. 05' DeVille-Starts only if gas pressed, stalls out after release. P0300 code random misfire This is a discussion on P0300 code random misfire within the General Help forums, part of the LSx Technical Help Section category; I'm talking about the two big bulk head connectors that run into the ECM @ the passengers side of the. After a few minutes, the CEL came on with the codes: P1399, P0301, P0304, P0300. Just had the same symptoms and codes. They decarbonized and added additive. P0300 - Random Misfire Detected Description: This DTC sets when the misfire detection monitor detects an engine misfire in multiple cylinders or the PCM cannot identify which cylinder is misfiring. Engine misfire is caused by an incomplete combustion process within the cylinder. It was throwing numerous codes which I fixed most of them, but the persistent codes have been. It does not blink when the car is not moving even if the same RPM level is reached. 2L VORTEC GEN III, GEN IV, V-8 Engine. I have a 2003 cadillac deville with 169,000 miles. By servyoutube Last updated. Drove the car for about 17 miles with the goal of perhaps more codes would appear in order support a better assessment. This van will be driven to a jobsite and idles all day. My 2000 CRV started running rough very suddenly a few days ago. It stands for: P0300: Random Multiple Misfire Detected. Jump to Latest Follow (car was still warm) and the engine began to misfire and vibrate causing a very rough idle and the engine to shut-off after about 5 seconds. If the engine speed fluctuates enough to cause the Crankshaft Position (CKP) sensor signal to vary, the Engine Control Module (ECM) can determine that a misfire is occurring. had coil 2 and all spark plugs replaced. What Does the P0300 Code Mean? The P0300 trouble code indicates that one or more engine cylinders have misfired. DTCs revealed P0300 GENERAL MISFIRE. Now, there a misfire dealing with, I believe, another cylinder. 2004 Cadillac CTS 97-05 Vehicles with 4. The efficient burning of fuel is essential to engine operation as the combustion of fuel is what provides the energy to power the engine. You read / get the codes read and they are either a single P0300 or P0301 P0302 P0303 P0304 P0305 P0306 or any combination. P0301 Cylinder #1 Misfire. P0305 Cylinder #5 Misfire. It has since come back on twice in the past week. 6 LGW, LGX All Cadillac CTS 2016 - 2017 All All 3. Engine misfire is caused by an incomplete combustion process within the cylinder. If the engine speed fluctuates enough to cause the Crankshaft Position (CKP) sensor signal to vary, the Engine Control Module (ECM) can determine that a misfire is occurring. has 91000 miles. as it starts to warm it starts to miss. A P0300 diagnostic code indicates a random or multiple misfire. 8t has just begun misfireing when accelerating, engine management light is flashing. If the computer detects an individual cylinder is not firing properly a P0301 would set for cylinder one. What to do when the fix had not worked?. 2007 Cadillac CTS Engine Technical Service Bulletins TSB Number: communicates information that will need to be provided to tac to aid in diagnosing if a vehicle comes in with misfire and DTC codes P0300 - P0308 communication provides information to the technician on the step to diagnose and repair vehicles that may have engine misfire. Random misfire. I have a misfire with a p0300 code. if the generated code is P0302, the number 2 indicates that cylinder number 2 has a misfire. picks up a miss at Wide open throttle, then immediately drops those inj drivers until key is cycled. Call Us: +1 (714) 249-4800 Text Us: +1 (415) 849-4800 Text Us: +1 (415) 849-4800. Drivers with a misfire will often complain about a lack of power, sputtering or rough engine idle. com Address: EricTheCarGuyP. Swung by AAP to read the code and got a P0300 code, random misfire - replace timing chain. 4 Coolant(F) 167 ST FTRM 1 -0. I removed a spark plug wire and an injector clip in order to make the engine misfire and cause a P0300 code in the computer. You will see why later in this article. -Code P0306 (Misfire #6 Cylinder)-Rough Idle-Flashing Check engine light-Service Stabilitrak/Traction Control Messages-Hard gear shift from 1-2,2-3 also on downshift-Very high oil Consumption (3 quarts low) Tried:-New plugs,wires,coils-Checked for spark-Ensured all connections were tight Need to try:-Check for vacuum leaks. How do you test coil packs. 2004-2007 Cadillac CTS or SRX Engine Computer Repair Kit. What Does Code P0300 Mean? OBD II fault code P0300 is a generic code that is defined as " Random/Multiple Cylinder Misfire Detected", and is set when the PCM (Powertrain Control Module) detects either randomly misfiring cylinders, or misfires on multiple cylinders. P0300 is a diagnostic trouble code (DTC) for "Random/Multiple Cylinder Misfire Detected". as it starts to warm it starts to miss. If you shop at Amazon. This one now has 65,000 miles on it. As the vehicle was out of warranty, I took it to the local parts store, read the codes (P0300 and P0303 misfire codes were present) the 2nd code localized the misfire to cylinder 3. It means that the powertrain control module (PCM) has detected a rough engine idle during cold start. A misfire condition that sets a diagnostic trouble code (P0301, P0302, P0303, P0304, P0305, P0306, P0307, P0308) and thus illuminates the check engine light is one that is usually easy to diagnose and repair. 6L with 71000 miles. Pulled that plug and it was damp with fuel. The check engine light came on, I checked the codes got : p0300, p0158, and p0138. vehicle only misses at an idle. car runs prefectly no misfire idleing or under load. Isuzu Trooper Engine Misfire. 7 LT FTRM 1 -7. The repair shop had diagnosed the coil pack as faulty and fitted a new unit with plugs, but this made no difference to the problem. These problems result mainly from poor combustion, which stifles the engine. If the engine speed fluctuates enough to cause the Crankshaft Position sensor signal to vary, the Engine Control Module can determine that a misfire is occurring. P0304: Misfire Detected → Cylinder 4 P0304 is certainly a cause for concern, and should be considered a threat to the drivability your CTS. P0305 – Misfire on cylinder #5. Lynn Richardson - Duration: 54:48. If the "new" engine was sitting around in storage for many years, you may have a problem with one or more fuel injectors. P0298 Engine Oil Over Temperature P0300 Random/Multiple Cylinder Misfire Detected P0301 Cylinder 1 Misfire Detected P0302 Cylinder 2 Misfire Detected P0303 Cylinder 3 Misfire Detected P0304 Cylinder 4 Misfire Detected P0305 Cylinder 5 Misfire Detected P0306 Cylinder 6 Misfire Detected P0307 Cylinder 7 Misfire Detected. Subject: Information on Engine Misfire MIL/SES Light Illuminated or Flashing DTC P0300, P0301, P0302, P0303, P0304, P0305, P0306, P0307, P0308, P0420 or P0430 Models: 1999-2007 Cadillac, Chevrolet, GMC Full-Size Pickup and/or Utility Trucks with 4. I've replaced the fuel injector and spark plug on cylinder 2. Along with louder noises, a misfiring engine can produce a foul smell, similar to gasoline, but with a combination of coolant and engine oil. The misfire of the engine cylinder causes the engine speed to fluctuate. An engine misfire happens when one of the cylinders in your engine fails to function properly. 8 liter engine. This apparently happened on start up, and doesn't seem to have any issues running. His And Her Money 389,878 views. FAQ; OBD Codes Forum. Less common reasons for an engine misfire include a faulty fuel injector, an intake air leak, insufficient cylinder pressure and incorrect fuel pressure. Jump to Latest Follow 1 - 10 of 10 Posts. Cadillac CTS First Generation Forum - 2003 - 2007. Call Us: +1 (714) 249-4800 Text Us: +1 (415) 849-4800 Text Us: +1 (415) 849-4800. I haven't troubleshot it any further. Cadillac CTS Check Engine Light Flashing Misfire. Quick Navigation Magnum General Discussion (2005 - 2008). 6L (8th 500 x 500 · 37 kB · jpeg Source. 0 hour of labor. The Crankshaft Position sensor works in conjunction with a 24X reluctor wheel on the crankshaft. The engine idles very rough and you can definitely tell it's a misfire from the exhaust end. P0308 indicates that cylinder number 8 is experiencing misfires. Engine may stumble or miss Engine may be hard to start you may notice no issues Cause Failing spark plugs or spark plug wires Bad coil or coil pack. 6l p0300, bad spark plug, Cadillac DeVille P0300, cadillac misfire diagnostic, code p0300, DIY, fuel injector activation, fuel injector test, how to fix p0300, how to test p0300, ignition coil test, P0300, p0300 code, spark plug test Leave a comment. Joined 2. Forums > 1991 - 1999 Tahoe & Yukon Models. This time it is a flashing engine service light that happened at 100km/hr. By servyoutube Last updated. The loss of 25% of the engine's power output is the equivalent of a horse trying to run on three legs. I am not sure how long, as when I noticed it, it stopped. Javier S · Registered. P0304: Misfire Detected → Cylinder 4 P0304 is certainly a cause for concern, and should be considered a threat to the drivability your CTS. OBD2 Code P0303 Cadillac definition: A P0303 Cadillac code means that the the car’s computer has detected that one of the engine’s cylinders is not firing properly. Lynn Richardson - Duration: 54:48. I need HELP! The engine light stays on but when I go to accelerate engine light blinks. Only cylinder 4 when car is warm, in gear, stopped or slight coast. It will often be accompanied by codes P0301-P0308. When a cylinder misfire occurs, ECU (Engine Control Unit) will generate one or several DTC’s (Diagnostic Trouble Codes) such as P0301, P0302, P0303, P0304, P0305, P0306, P0307, P0308, P0309, P0310, P0311, or P0312. DTC P0300 Engine Misfire Detected. Misfire Codes P0300 P0301 P0302 P0303 P0304 / Moisture in Distributor Cap [S70][1998] posted by Bill1959 on Tue Apr 1 21:45 CST 2014 > V Users marked in green are currently online. At that point, I performed a running exhaust pulse test on the vehicle. Now I got a P0300 code random misfire. The only thing that's been changed recently were the spark plugs and the right MM (within the last week). I had a P0300 on. All the other messages are for misfire of a particular cylinder indicated by the last digit. It didn't give me a problem right away. Our certified mobile mechanics can come to your home or office to perform the Check Engine Light diagnostic. 5-liter four-cylinder base engine. Yesterday on the way to work my 2000 Chevrolet Silverado 1500 4WD with the 4. Javier S · Registered. 0 liter 3ZR. I have a Code P0300 which is a Random Misfire Code. 0 Gen III V8 Engines and Misfires On One Bank. The car has about 119000 miles. Description: How does a P0300 code trigger the check engine light? This code will trigger the check engine light as follows: The misfire detection monitor, a software strategy built into the computer, is designed to detect an engine misfire. The check engine light had come on, with P0300 engine misfire code. Jump to Latest Follow 1 - 1 of 1 Posts. I have a misfire with a p0300 code. 05' DeVille-Starts only if gas pressed, stalls out after release. 2000 Cadillac Catera Engine and Engine Cooling TSB Details …; 2000 Cadillac Catera Others TSB Details …; 2000 Cadillac DeVille Engine and Engine Cooling TSB Details …. And those are all history codes. 5-liter four-cylinder base engine. 4500 miles, and had the P0300 Cylinder misfire code 2 times now. Meaning of P0300 engine trouble code is a kind of powertrain trouble code and theoretically you can drive for a few weeks or even months with a broken MAF sensor. I have tried to check for vacuum leaks, but I am not very familiar with this engine. This did nothing for me. 5L EcoBoost in your shop with misfire code s P0300-0306 pull the plugs and coil boots and look for carbon tracks on the insulator of the plugs. If the last digit is a number other than zero, it corresponds to the cylinder number that is misfiring. Code P0300 - Engine Misfire Detected. My GFs Leon 1. For instance cylinder 1 misfire is P0301, cylinder 2 is P0302 etc. GMC Yukon Forum | Tahoe Z71 | Cadillac Escalade - Tahoe Yukon Forum. P0300 random misfires Diagnose P0300 random misfires. 0L I've been reading for weeks on these humble forums about all the P0300 trouble codes. The P0300 misfires, check engine light, and possible codes occur during deceleration which doesn’t make much sense considering engine load is low or non-existent in this mode. Cadillac CTS First Generation Forum - 2003 - 2007. P0300 and P0306 Got in the car this morning and noticed a check engine light. The repair shop had diagnosed the coil pack as faulty and fitted a new unit with plugs, but this made no difference to the problem. I own a 2005 Cadillac CTS 3. Having an issue with Vauxhall Zafira 1. The engine coolant temperature (ECT) is between -7 and +130°C (+19 and +266°F). 12/04/13 check engine light with history of misfire on cylinder #2 and #4. My 2000 CRV started running rough very suddenly a few days ago. Anyone else have one of these happen on the traverse or one of the GMC Acadias or Buick enclaves? 3. This is one of the more serious diagnostic codes a vehicle computer can set. 0, random after being on hoghway highway, yes fixing myself - Answered by a verified Cadillac Mechanic. However, the code P0300 displays as "random/multiple cylinder misfire detected" which means its more than one. This is due to the fact that gaskets tend to age and often the oil in the spark plugs is cause by failing valve cover gasket. I was able to get the car idling decently and get the car home. Check Engine Light Code P0300 Random/Multiple Cylinder Misfire Detected. The check engine light came on, I checked the codes got : p0300, p0158, and p0138. Engine MIL was on. Misfires trigger the check engine light to flash on and off. Javier S · Registered. I read it and it was a P0300 Random/Multiple Misfire. Mazda rx8 2. The P0300 code is a random misfire code and may or may not be the above. One or more misfire codes will be stored in the car or mini-van's computer memory (if OBD II equipped). It uses programmed data as well as input from sensors that monitor engine coolant temperature, engine speed, load, throttle position and others to make timing adjustments. 6l misfire, 4. 6 LGW, LGX All Cadillac CTS 2016 - 2017 All All 3. I have a 2004 Cadillac deville that has the P0300 code and flashing check engine light on it was missing and sputtering. Usually, though, it’s rust between the block and clamp that retains the sensor in the block. Spark plugs were checked and #3 is fuel fouled. We have changed coils, plugs, oil filter. 2015+ S550 Mustang Forum (GT, EcoBoost, GT350, GT500, Bullitt) - Mustang6G. The p0141 is a rear O2 sensor. I am still getting a P0300 code (multilple engine misfire) and the check engine light blinks only when the car is moving. By servyoutube Last updated. I was driving home today and my engine light came on, I used the Dash Hawk and it said I had a Random Misfire code P0300, P0301, P0302, P0303, P0304. moved the coil w … read more. If the last digit is a number other than zero, it corresponds to the cylinder number that is misfiring. 6 LGX All Cadillac XT5 2017 All All 3. -Code P0306 (Misfire #6 Cylinder)-Rough Idle-Flashing Check engine light-Service Stabilitrak/Traction Control Messages-Hard gear shift from 1-2,2-3 also on downshift-Very high oil Consumption (3 quarts low) Tried:-New plugs,wires,coils-Checked for spark-Ensured all connections were tight Need to try:-Check for vacuum leaks. PATH: Diagnostics > Diagnostic Routines > Powertrain > Engine Controls - 4. What to do when the fix had not worked?. Jump to Latest Follow 1 - 10 of 10 Posts. I am not sure how long, as when I noticed it, it stopped. Most vehicles it really doesn't matter too much but in some occasions it can help get better benefits of doing a full tune up. Symptoms are a misfire at idle on cylinders 2, 4, 6, 8, P0300 on the scan tool. Two of my plugs were oil fouled before changing (#2 and 4 from driver's to passenger side) so I'm assuming the valve cover gasket needs to be replaced. Also the Track Light is on and the engine runs like it has jumped time or has fouled plugs. toyota, celica. If the engine speed fluctuates enough to cause the crankshaft position (CKP) sensor (POS) signal to vary, ECM can determine that a misfire is occurring. Testing a misfire condition or misfire codes (P0300, P0301, P0302, P0303, P0304, P0305, P0306) on a 3. 0 The cost of diagnosing the P0300 CADILLAC code is 1. When you have a misfire, the engine will run off balance, creating a powerful vibration through the body of the car, and the amount of power the. 2004-2007 Cadillac CTS or SRX Engine Computer Repair Kit. I narrowed it down to what I thought was spark plugs and 2 bad coils, changed them and it helped for awhile (about two miles). So, that's a good. Engine Misfire : Cadillac STS 3. 6L with 71000 miles. I was looking to purchasing an older truck and the seller informed me that "I should check my tail lights - TRUST ME". P0301 - Cylinder 1 misfire. For the past week or 2 had a check engine light but I didn't get a chance to scan it. P0171 and P0300. In a modern combustion engine, if more than one cylinder misfires, this will increase or decrease the revolutions per minute (RPM) of the crankshaft. P0304 – Misfire on cylinder #4. com database, we found four main sources of problems with Cadillac 5. Hello, I have a Lincoln LS 2001 V8 and I had the engine serviced some months ago for a misfire in the engine. The only modifications recently made was a ZL1 lid install. My distributer is about 1. What Does Code P0300 Mean? OBD II fault code P0300 is a generic code that is defined as "Cylinder Misfire Detected Random Cylinders", and is set when the PCM (Powertrain Control Module) detects either a random misfire on one cylinder, or multiple cylinders that misfire randomly. 2003 Cadillac CTS / Misfire codes p0303 and p0300; Misfire codes P0303 and P0300 (2003 Cadillac CTS) P0303 was a misfire code that pertained specifically to #3 cylinder, you have taken car of that by replacing the coil and spark plug. PIP5493A Misfire with DTC's P0300, P0301-P0306 Models Brand: Model: Model Years: VIN: Engine: Transmissions: from to Buick LaCrosse 2017 All All 3. When the startup ECT is colder than -7°C (+19°F), this diagnostic will be delayed until the ECT is warmer than. P0300 Diagnostic Code - Random Misfire What does that mean? Basically this means that the the car's computer has detected that not all of the engine's cylinders are firing properly. Has the dealer tried reflashing the PCM?. I have replaced ignition coil on cylinder 4 on drivers side, which seemed to have the most misfires, but it seems to not make any difference. Not vehicle related p0300. If you set codes for a misfire on a particular cylinder, consider yourself lucky. These trouble codes can be cleared automaticly once the. [FIXED] P0300 Misfire on Bank 2 was created by dbadge This is a fun one so far, I've had no luck on fixing this so far. If the engine speed fluctuates enough to cause the Crankshaft Position (CKP) sensor signal to vary, the Engine Control Module (ECM) can determine that a misfire is occurring. 6L with 71000 miles. the number after the 3 indicated the misfiring cylinder. It didn't single out a particular cylinder or sound and feel like I had a dead cylinder so I did a check for vacuum leaks nothing. I too had to replace an engine at 145,000 miles. Cadillac CTS First Generation Forum - 2003 - 2007. Replacing coil pack and plugs had not cured the fault. P0300 code random misfire This is a discussion on P0300 code random misfire within the General Help forums, part of the LSx Technical Help Section category; I'm talking about the two big bulk head connectors that run into the ECM @ the passengers side of the. 1997 Chevy Suburban 5 Cylinder Misfire of the most common causes of misfires and misfire codes p0300 p0301 560 x 350 · 70 kB · jpeg Source 2001 Cadillac STS Water Pump 2001 STS: Misfiring and P0300 - Page 2 800 x 600 · 99 kB · jpeg Source. 0, random after being on hoghway highway, yes fixing myself - Answered by a verified Cadillac Mechanic. P0301 through P0304 indicate misfires pertaining to individual cylinders, i. Tune ups included. Joined 2. The check engine light had come on, with P0300 engine misfire code. P0300 is certainly a cause for concern, and can be a threat to the drivability the Cadillac DTS. My car has 65k on 04' cadilac srx and runs rough. Follow the Repair. GMC Acadia P0300 Engine Trouble Code GMC Acadia P0300 code can be about replacing a broken oxygen sensor can eventually lead to a busted catalytic convertor which can cost upwards of $2,000. Engine MIL was on. I made the mistake of washing down the engine with a water hose. Most vehicles it really doesn't matter too much but in some occasions it can help get better benefits of doing a full tune up. Discuss it at Forum View This TSB. When the startup ECT is colder than -7°C (+19°F), this diagnostic will be delayed until the ECT is warmer than. If the engine speed fluctuates enough to cause the Crankshaft Position sensor signal to vary, the Engine Control Module can determine that a misfire is occurring. Last two digits of the DTC codes indicate what cylinder is misfiring. com (for anything), use this link to support OBD-Codes. I have used a old school timing light on the coil packs and it shows steady firing. 6l p0300, bad spark plug, Cadillac DeVille P0300, cadillac misfire diagnostic, code p0300, DIY, fuel injector activation, fuel injector test, how to fix p0300, how to test p0300, ignition coil test, P0300, p0300 code, spark plug test Leave a comment. When the misfire monitor detects a misfire, it will trigger the check engine light with the specific cylinder number as the last digit in the P030X code. 2L VORTEC GEN III, GEN IV, V-8 Engine. The first is cylinder 1 misfire, the other one is cylinder 5 misfire, I didn't get a printout on the 300 but it probably is another cylinder misfire. These trouble codes can be cleared automaticly once the. If you find a P0300 code, it means the misfire is random and is moving around from cylinder to cylinder. You may find DTC P0300 (Engine Misfire Detected) set along with a misfire and low compression in one or more cylinders. Engine Misfire/Tick Noise, Malfunction Indicator Lamp (MIL) On, DTC P0300 Set Models: 2015-2016 Cadillac Escalade: 2016 Cadillac CTS-V: 2014 Chevrolet Silverado 1500: 2014 - 2016 Chevrolet Corvette: 2015 - 2016 Chevrolet Silverado, Suburban, Tahoe: 2016 Chevrolet Camaro: 2014 GMC Sierra 1500: 2015 - 2016 GMC Sierra, Yukon, Yukon XL. DTC P0300 (Engine Misfire Detected) may set after performing engine repairs on the following vehicles equipped with a V8 engine: • 2004-2007 Rainier • 2008-2009 LaCrosse, Allure (Canada Only). 4500 miles, and had the P0300 Cylinder misfire code 2 times now. The Crankshaft Position sensor is mounted through the side of the engine block at the rear of Bank 2 behind the starter assembly. Possible Causes: Damaged camshaft position (CMP) sensor; Low fuel (less than 1/8 tank) Stuck open exhaust gas recirculation (EGR) valve; Blocked EGR. I disconnect my battery any time i work on the engine. It has codes p0443, p0300, p0302, and p0202. Cylinder 4 Misfire Detected - Same as DTC P0300. Cadillac CTS Forums 2003-2019. Code P0174 – Fuel System to Lean Bank 2 Code P0158 – O2 Signal High Bank 2 Sensor 2. 6 L 302 hp Gas Another common cause would be a fuel delivery issue causing the engine to misfire causing a P0300 code (or any misfire related code) to be stored in the computer. This is due to the fact that gaskets tend to age and often the oil in the spark plugs is cause by failing valve cover gasket. 0L with occasionally very intermittent P0306 popping up to start then eventually P0304. A P0300 diagnostic code indicates a random or multiple misfire. It can be a lack of fuel or too much fuel. I own a 2005 Cadillac CTS 3. engine runs fine cold. OBD2 Code P0303 Cadillac definition: A P0303 Cadillac code means that the the car’s computer has detected that one of the engine’s cylinders is not firing properly. Categories Automotive Repair Videos, Check Engine Light, DIY Auto Repair Tags 4. Sometimes, the engine control unit cannot detect which cylinder the misfire occurs on and it will display the DTC code P0300 (random misfire). I was driving it up a hill the other day and all of a sudden it started running like crap and the engine light is blinking. The code P0300 means that there is a random misfire between cylinder 1 and cylinder 2, as they occur not all the time. The check engine light had come on, with P0300 engine misfire code. Sixity Auto Direct stands for value, selection, and quality. It was extremely cold in our area (probably around 15F this morning, with the garage aound 30F). Basically, this P0300 code means that the car's computer has detected that not all of the engine's cylinders are firing properly. The misfire of the engine cylinder causes the engine speed to fluctuate. If the last digit is a number other than zero, it corresponds to the cylinder number that is misfiring. 4l misfire P0305 P0304 P0300 P0316 P0171 After having all of my sparkplugs replaced my truck was running much worse. I was going about 40 mph and I felt a little jerk in my engine and my CEL started to flash. 2L VORTEC GEN III, GEN IV, V-8 Engine. Replaced all spark. If I load to 1300+, in N, regular driving and even WOT, no misfires. Having an issue with Vauxhall Zafira 1. P0302 CADILLAC Meaning When a misfire occurs, engine speed will fluctuate. When the misfire monitor detects a misfire, it will trigger the check engine light with the specific cylinder number as the last digit in the P030X code. While researching misfires in ShopKeyPro. These problems result mainly from poor combustion, which stifles the engine. Engine hesitation P0300 2006 NISSAN MAXIMA Description When a misfire occurs, engine speed will fluctuate. NOTE Applicable vehicles: Seville (VIN K) DTC P0300. This preliminary information communication provides information to the technician on the step to diagnose and repair vehicles that may have engine misfire and check engine light with any or all cylinder misfires only on deceleration. DTC DETECTION LOGIC. In March 2008 I bought an engine for a Dodge Neon from a local junkyard. So, you are faced with diagnosing a stored a code P050D. Pulling codes, it was showing a P0300. Trouble codes OBD-II trouble codes P0300 through P0304 refer to an engine misfire. Got it scanned the other night and got the P0300 code (multiple cylinders misfiring). If the engine speed fluctuates enough to cause the Crankshaft Position (CKP) sensor signal to vary, the Engine Control Module (ECM) can determine that a misfire is occurring. P0300 random misfire trouble code Fix a P0300 random misfire code on a GM or GMC vehicle. Sometimes, the engine control unit cannot detect which cylinder the misfire occurs on and it will display the DTC code P0300 (random misfire). car runs prefectly no misfire idleing or under load. P0300 Multiple Cylinder Misfire Today we're going to look at one of the most common, and one of the most confounding, Pcodes that can cause your check engine light to come on. 2010 Cadillac SRX Premium 2. For instance cylinder 1 misfire is P0301, cylinder 2 is P0302 etc. We demonstrated how the spark plug well was full of oil on this car and this was causing engine misfire and you can get multiple misfire codes any thing from P0300 to P0301, P0302, P0303, P0304 on a 4 cylinder engine. P0304 – Misfire on cylinder #4. It recently began misfiring while I was driving usually on the highway at speed and never at idle. 6L with 71000 miles. OBD2 Code P0300 Cadillac definition: Basically this means that the the car’s computer has detected that not all of the engine’s cylinders are firing properly. The following TSBs of Cadillac are related to DTC P0300. I have had it almost two years with no problems. No vacum leak found. What to do when the fix had not worked?. Code: P0300 may also be accompanied by a 301-312. It stands for: P0304: Misfire Detected → Cylinder 4. A laptop-based scan tool (and some tablet-based scan tools) or a technician-quality scan tool will show the miss counts. Hello and thanks for your question. One problem is vacuum leaks in the intake tubing or hoses attached to the intake manifold. P0300 means "Multiple Cylinder Misfire" and the laymen definition isn't much different. 8L V8 Vortec engine started flashing a check engine light. The Crankshaft Position sensor works in conjunction with a 24X reluctor wheel on the crankshaft. Drove the car for about 17 miles with the goal of perhaps more codes would appear in order support a better assessment. Tune it up, new ac/delco plugs, good plug wires, fuel filter and don't forget to look at the cabin and air filters as well. Cadillac CTS Forums 2003-2019. This time it is a flashing engine service light that happened at 100km/hr. 6 192ps 2005 model,i bought it as a non runner as i suspected just flooded out,got it de-flooded and started but has a slight misfire,code reader says p0302 but not being a conventional engine i was wondering if this relates to a particular plug/coil/lead or does it just signify,rotor 1 or rotor 2,also how are the coil packs. It can be a lack of fuel or too much fuel. Call Us: +1 (714) 249-4800 Text Us: +1 (415) 849-4800 Text Us: +1 (415) 849-4800. Multiple cylinder misfire is a common occurrence with a lean air-fuel. 05' DeVille-Starts only if gas pressed, stalls out after release. I have replaced ignition coil on cylinder 4 on drivers side, which seemed to have the most misfires, but it seems to not make any difference. Jump to Latest Follow 1 - 10 of 10 Posts. P0301 – Misfire on cylinder #1. I own a 2005 Cadillac CTS 3. 0 hour of labor. My GFs Leon 1. Figure 2: Examples of light vertical marks visible on the cylinder wall: None of the marks in the cylinder walls could be felt with the fingernail and engine replacement is not recommended. A P0300 diagnostic code indicates a random or multiple misfire. 2006 Yamaha F115 Engine Misfire? August 21st, 2019, 10:00 PM. DTC P0300 Engine Misfire Detected. However, the code P0300 displays as "random/multiple cylinder misfire detected" which means its more than one. They can be very mysterious, and expensive if not addressed logically. 05' DeVille-Starts only if gas pressed, stalls out after release. The engine may be running too lean, due to a leaking intake manifold. It does not blink when the car is not moving even if the same RPM level is reached. If the engine speed fluctuates enough to cause the Crankshaft Position (CKP) sensor signal to vary, the Engine Control Module (ECM) can determine that a misfire is occurring. It describes a cold engine idle misfire, with DTCs P0171 P0174 or P0300. On Saturday (this all happened on a Friday) I went to my local auto parts store and borrowed a code reader and pulled 4 codes P0300, P0301,P0303,P0305. Forums > 1991 - 1999 Tahoe & Yukon Models. if the generated code is P0302, the number 2 indicates that cylinder number 2 has a misfire. I started with a coil amp test hoping for direction. 4 of them each with 2 wires connected to it. P0301 Cylinder #1 Misfire. The check engine light had come on, with P0300 engine misfire code. Engine Misfire : Cadillac STS 3. 7 LT FTRM 1 -7. 4L Spark Plug Wire Routing; Check Engine Light Code P0300 On GM 2. Brand new on the market and it quickly can diagnose a misfire from the plug or the coil pack. Could be 303 also. Yesterday on the way to work my 2000 Chevrolet Silverado 1500 4WD with the 4. Back to the miss fire issue. It keeps throwing pcm p0300 codes, engine light, and idles rough at stop signs and when parked.