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P0304 Diagnostic Trouble Code Discussion for November 2009

Cylinder 4 Misfire Detected


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Trouble Ticket Help Requests for DTC P0304
Help Request Posted
2003 Land Rover Discovery HSE 4.6L Poor Idle Quality, Misfire, MIL Lamp on VIN: SALTY16443
P0304: . please help. we have replaced camshaft,lifters,timing chain and spark plugs. we have good spark,fuel and valves seem to no be sticking,good compression and does not drop. what would be your next step? fuel trim all reads negative by the scan tool.
November 03, 2009
2007 Chevrolet Silverado 1500 Classic LS 4.3L Misfire VIN: 1GCEK14X87
P0304: Cylinder 4 Misfire Detected. hi everyone,this truck misfires at 1500 rpms faithfully the fuel trim no. are not high.it acts like a lean condition caused by a egr but there is no valve.only thing i see is the cam retard is a -7 degrees.would a ign module cause this?any help would be great,...
November 05, 2009
1996 Honda Accord EX 2.2L Poor Idle Quality, Misfire, MIL Lamp on VIN: 1HGCD5652T
P0304: Cylinder 4 Misfire Detected. thanks for any help in advance and here are the vehicle symptoms: when car is first started(cold soak) engine runs fine but once it goes into closed loop idle gets a little rough but not misfiring then as soon as it is put in gear and a little load applied eng...
November 05, 2009
2003 Land Rover Discovery HSE 4.6L Poor Idle Quality, Misfire, MIL Lamp on VIN: SALTY16443
P0304: . please help. we have replaced camshaft,lifters,timing chain and spark plugs. we have good spark,fuel and valves seem to no be sticking,good compression and does not drop. what would be your next step? fuel trim all reads negative by the scan tool.
November 05, 2009
2000 Volkswagen Jetta GL 2.0L Poor Idle Quality, Cuts out, Misfire, MIL Lamp on VIN: 3VWSC29M2Y
P0304: Cyl4 Misfire. Howdy Techs, here is a weird German VW problem, When cylinder # 4 was misfiring, fuel pump relay would click rapidly causing multiple misfires. Pin testing relay socket no problems found. Has anyone come across this ? Want to ship the vehicle out. Have driven ...
November 05, 2009
1996 Jeep Grand Cherokee Limited 5.2L Poor Idle Quality, Misfire, MIL Lamp on VIN: 1J4GZ78Y3T
P0304: Cylinder 4 Misfire Detected. This vehicle belongs to a friend of mine.He says the problem started when he left the engine idling one day he had visited a friend.When he came out the engine was misfiring.It will misfire at idle or at highway speeds.When I got the vehicle I pulled the spark...
November 06, 2009
2003 Mazda 6 S 3.0L Misfire, MIL Lamp on VIN: 1YUFP80D13
P0304: Cylinder 4 Misfire Detected. We have this Mazda that is setting a cyl. 4 misfire code only when held above 3000 rpm. I have swapped coils, injectors, spark plugs, and replaced uppper plenum seals with no change. I have confirmed pcm is identifying correct cylinder by removing coil from pl...
November 06, 2009
2000 Volkswagen Jetta GL 2.0L Poor Idle Quality, Cuts out, Misfire, MIL Lamp on VIN: 3VWSC29M2Y
P0304: Cyl4 Misfire. Howdy Techs, here is a weird German VW problem, When cylinder # 4 was misfiring, fuel pump relay would click rapidly causing multiple misfires. Pin testing relay socket no problems found. Has anyone come across this ? Want to ship the vehicle out. Have driven ...
November 06, 2009
1996 BMW 740iL 4.4L Poor Idle Quality, Misfire, MIL Lamp on VIN: WBAGJ8329T
P0304: misfire 4. Good morning! We have been having some bad luck with this 7 in our shop. Car came in for a lf wheel bearing and rough running, sounded simple enough! We did bearing, and started troubleshooting the rough idle. We got 2 misfire codes for #1 and #3 cylinders, sm...
November 09, 2009
2003 Mazda 6 S 3.0L Misfire, MIL Lamp on VIN: 1YUFP80D13
P0304: Cylinder 4 Misfire Detected. We have this Mazda that is setting a cyl. 4 misfire code only when held above 3000 rpm. I have swapped coils, injectors, spark plugs, and replaced uppper plenum seals with no change. I have confirmed pcm is identifying correct cylinder by removing coil from pl...
November 09, 2009
2000 Audi A6 Quattro 2.7L Misfire, MIL Lamp on VIN: WAUED24B9Y
P0304: Cylinder 4 misfire. ... engine light complaint. Scan revealed 1 code (P0304) for a cylinder #4 misfire. So far we have replaced spark plugs, fuel filter, air filter mostly for basic maintance. We have swapped ignition coils between cylinders and the problem persists at the sa...
November 10, 2009
2005 Acura RL 3.5L Misfire VIN: JH4KB16505
P0304: Cylinder 4 Misfire Detected. help!!! this car came from another shop. when you first start the car it runs rough and mis-fires. when you give it gas, it sputters then revs ok and then idles ok. if you drive it up the road easily, it is ok, but under a load it mis-fires. we have check fue...
November 11, 2009
2004 Toyota Sienna LE 3.3L MIL Lamp on VIN: 5TDZA23C84
P0304: Cylinder 4 Misfire Detected. ... MIL light on drives good. pull code p0300 thru p0306. replaced all coils oem. shipped now back same codes . this so called misfireing only happens at 60+mph speeds and will flash the MIL light, but on test drive watching mi...
November 13, 2009
2002 Ford Taurus SE 4-Valve 3.0L Misfire, MIL Lamp on VIN: 1FNHP56SX2
... months ago with complaint of no power, rough idle, & Ck engine light on. The car ran fine for me. I changed the plugs and filters & cleared codes (Misfire Codes). When the vehicle came back in for brake work the light was on and customer said the c...
November 15, 2009
2000 Chevrolet Blazer LS 4.3L Misfire VIN: 1GNCT18WXY
P0304: freeze frame. vehicle missfires on heavy acceleration. very intermittant and seems to only misfire on cyl 4 and 3
November 17, 2009
1999 Ford Explorer XLT 4.0L Misfire, MIL Lamp on VIN: 1FMZU34X9Z
P0304: cyl. 4 misfire. Hey guys, hope you can help, this one comes back a LOT. There is a miss mostly on cyl. 4 and sometimes on cyl. 6. The vehicle has been here many times and everything is checked and rechecked by different techs with nothing ever found. We have done injector and...
November 19, 2009
2005 Subaru Legacy GT Limited 2.5L Poor Idle Quality, Misfire, MIL Lamp on VIN: 4S3BL67635
P0304: Cylinder 4 Misfire Detected. customer came in first with a cyl # 3 missfire, codes were just erased by someone else - so monitors had not ran completely. i requested that the customer return when all monitors had ran. customer put new plugs, switched coils around. no difference car runs w...
November 19, 2009
2005 Ford E-250 Super Duty 5.4L Misfire VIN: 1FTNE24L85
P0304: Misfire 4. Missing most of the time off idle on #4. Idles smooth. Tested the wires from PCM to coil and injector. Ran compression test and have 185 on 3 and 4. Running compression test have 65 to seventy five on 34 and 8. Did not check them all. Pulled valve cover to ins...
November 23, 2009
2001 GMC Sonoma SLS 4.3L Misfire, MIL Lamp on VIN: 1GTCS14W01
P0304: Cylinder 4 Misfire Detected. This GMC shows that there is a misfire on cylinder 4 as soon as the truck is raised off idle. The misfire counter counts rapidly on cylinder 4 above about 1400 rpm, when the engine speed is held steady. It does not count when idling or when revving quickly and...
November 23, 2009
2000 Honda Accord LX 3.0L Poor Idle Quality, Stall, Misfire, MIL Lamp on VIN: 1HGCG165XY
P0304: Cylinder 4 Misfire Detected. HELP! This vehicle driving me nuts.The customer came in complaining of runs rough after hotsoak.It seemed the problem was fuel related.Went through fix database and read about Honda tsb about replace the fuel pressure regulator and pcm.I can make it do it ever...
November 23, 2009
2001 GMC Sonoma SLS 4.3L Misfire, MIL Lamp on VIN: 1GTCS14W01
P0304: Cylinder 4 Misfire Detected. This GMC shows that there is a misfire on cylinder 4 as soon as the truck is raised off idle. The misfire counter counts rapidly on cylinder 4 above about 1400 rpm, when the engine speed is held steady. It does not count when idling or when revving quickly and...
November 24, 2009
2000 Ford Taurus SE 4-Valve 3.0L Misfire, MIL Lamp on VIN: 1FAFP56SXY
P0304: 4 misfire. Hello This Taurus runs good 90% of the tine. Then it will develop a severe lack of power, as it runs on 3 cylinders. It runs on only 1,2,and3 when it messes up. The engine light will flash, suddenly it straightens out and runs great. It has COP, and when it w...
November 30, 2009
2003 Land Rover Discovery HSE 4.6L Poor Idle Quality, Misfire, MIL Lamp on VIN: SALTY16443
P0304: . please help. we have replaced camshaft,lifters,timing chain and spark plugs. we have good spark,fuel and valves seem to no be sticking,good compression and does not drop. what would be your next step? fuel trim all reads negative by the scan tool.
November 03, 2009
2007 Chevrolet Silverado 1500 Classic LS 4.3L Misfire VIN: 1GCEK14X87
P0304: Cylinder 4 Misfire Detected. hi everyone,this truck misfires at 1500 rpms faithfully the fuel trim no. are not high.it acts like a lean condition caused by a egr but there is no valve.only thing i see is the cam retard is a -7 degrees.would a ign module cause this?any help would be great,...
November 05, 2009
1996 Honda Accord EX 2.2L Poor Idle Quality, Misfire, MIL Lamp on VIN: 1HGCD5652T
P0304: Cylinder 4 Misfire Detected. thanks for any help in advance and here are the vehicle symptoms: when car is first started(cold soak) engine runs fine but once it goes into closed loop idle gets a little rough but not misfiring then as soon as it is put in gear and a little load applied eng...
November 05, 2009
2003 Land Rover Discovery HSE 4.6L Poor Idle Quality, Misfire, MIL Lamp on VIN: SALTY16443
P0304: . please help. we have replaced camshaft,lifters,timing chain and spark plugs. we have good spark,fuel and valves seem to no be sticking,good compression and does not drop. what would be your next step? fuel trim all reads negative by the scan tool.
November 05, 2009
2000 Volkswagen Jetta GL 2.0L Poor Idle Quality, Cuts out, Misfire, MIL Lamp on VIN: 3VWSC29M2Y
P0304: Cyl4 Misfire. Howdy Techs, here is a weird German VW problem, When cylinder # 4 was misfiring, fuel pump relay would click rapidly causing multiple misfires. Pin testing relay socket no problems found. Has anyone come across this ? Want to ship the vehicle out. Have driven ...
November 05, 2009
1996 Jeep Grand Cherokee Limited 5.2L Poor Idle Quality, Misfire, MIL Lamp on VIN: 1J4GZ78Y3T
P0304: Cylinder 4 Misfire Detected. This vehicle belongs to a friend of mine.He says the problem started when he left the engine idling one day he had visited a friend.When he came out the engine was misfiring.It will misfire at idle or at highway speeds.When I got the vehicle I pulled the spark...
November 06, 2009
2003 Mazda 6 S 3.0L Misfire, MIL Lamp on VIN: 1YUFP80D13
P0304: Cylinder 4 Misfire Detected. We have this Mazda that is setting a cyl. 4 misfire code only when held above 3000 rpm. I have swapped coils, injectors, spark plugs, and replaced uppper plenum seals with no change. I have confirmed pcm is identifying correct cylinder by removing coil from pl...
November 06, 2009
2000 Volkswagen Jetta GL 2.0L Poor Idle Quality, Cuts out, Misfire, MIL Lamp on VIN: 3VWSC29M2Y
P0304: Cyl4 Misfire. Howdy Techs, here is a weird German VW problem, When cylinder # 4 was misfiring, fuel pump relay would click rapidly causing multiple misfires. Pin testing relay socket no problems found. Has anyone come across this ? Want to ship the vehicle out. Have driven ...
November 06, 2009
1996 BMW 740iL 4.4L Poor Idle Quality, Misfire, MIL Lamp on VIN: WBAGJ8329T
P0304: misfire 4. Good morning! We have been having some bad luck with this 7 in our shop. Car came in for a lf wheel bearing and rough running, sounded simple enough! We did bearing, and started troubleshooting the rough idle. We got 2 misfire codes for #1 and #3 cylinders, sm...
November 09, 2009
2003 Mazda 6 S 3.0L Misfire, MIL Lamp on VIN: 1YUFP80D13
P0304: Cylinder 4 Misfire Detected. We have this Mazda that is setting a cyl. 4 misfire code only when held above 3000 rpm. I have swapped coils, injectors, spark plugs, and replaced uppper plenum seals with no change. I have confirmed pcm is identifying correct cylinder by removing coil from pl...
November 09, 2009
2000 Audi A6 Quattro 2.7L Misfire, MIL Lamp on VIN: WAUED24B9Y
P0304: Cylinder 4 misfire. ... engine light complaint. Scan revealed 1 code (P0304) for a cylinder #4 misfire. So far we have replaced spark plugs, fuel filter, air filter mostly for basic maintance. We have swapped ignition coils between cylinders and the problem persists at the sa...
November 10, 2009
2005 Acura RL 3.5L Misfire VIN: JH4KB16505
P0304: Cylinder 4 Misfire Detected. help!!! this car came from another shop. when you first start the car it runs rough and mis-fires. when you give it gas, it sputters then revs ok and then idles ok. if you drive it up the road easily, it is ok, but under a load it mis-fires. we have check fue...
November 11, 2009
2004 Toyota Sienna LE 3.3L MIL Lamp on VIN: 5TDZA23C84
P0304: Cylinder 4 Misfire Detected. ... MIL light on drives good. pull code p0300 thru p0306. replaced all coils oem. shipped now back same codes . this so called misfireing only happens at 60+mph speeds and will flash the MIL light, but on test drive watching mi...
November 13, 2009
2002 Ford Taurus SE 4-Valve 3.0L Misfire, MIL Lamp on VIN: 1FNHP56SX2
... months ago with complaint of no power, rough idle, & Ck engine light on. The car ran fine for me. I changed the plugs and filters & cleared codes (Misfire Codes). When the vehicle came back in for brake work the light was on and customer said the c...
November 15, 2009
2000 Chevrolet Blazer LS 4.3L Misfire VIN: 1GNCT18WXY
P0304: freeze frame. vehicle missfires on heavy acceleration. very intermittant and seems to only misfire on cyl 4 and 3
November 17, 2009
1999 Ford Explorer XLT 4.0L Misfire, MIL Lamp on VIN: 1FMZU34X9Z
P0304: cyl. 4 misfire. Hey guys, hope you can help, this one comes back a LOT. There is a miss mostly on cyl. 4 and sometimes on cyl. 6. The vehicle has been here many times and everything is checked and rechecked by different techs with nothing ever found. We have done injector and...
November 19, 2009
2005 Subaru Legacy GT Limited 2.5L Poor Idle Quality, Misfire, MIL Lamp on VIN: 4S3BL67635
P0304: Cylinder 4 Misfire Detected. customer came in first with a cyl # 3 missfire, codes were just erased by someone else - so monitors had not ran completely. i requested that the customer return when all monitors had ran. customer put new plugs, switched coils around. no difference car runs w...
November 19, 2009
2005 Ford E-250 Super Duty 5.4L Misfire VIN: 1FTNE24L85
P0304: Misfire 4. Missing most of the time off idle on #4. Idles smooth. Tested the wires from PCM to coil and injector. Ran compression test and have 185 on 3 and 4. Running compression test have 65 to seventy five on 34 and 8. Did not check them all. Pulled valve cover to ins...
November 23, 2009
2001 GMC Sonoma SLS 4.3L Misfire, MIL Lamp on VIN: 1GTCS14W01
P0304: Cylinder 4 Misfire Detected. This GMC shows that there is a misfire on cylinder 4 as soon as the truck is raised off idle. The misfire counter counts rapidly on cylinder 4 above about 1400 rpm, when the engine speed is held steady. It does not count when idling or when revving quickly and...
November 23, 2009
2000 Honda Accord LX 3.0L Poor Idle Quality, Stall, Misfire, MIL Lamp on VIN: 1HGCG165XY
P0304: Cylinder 4 Misfire Detected. HELP! This vehicle driving me nuts.The customer came in complaining of runs rough after hotsoak.It seemed the problem was fuel related.Went through fix database and read about Honda tsb about replace the fuel pressure regulator and pcm.I can make it do it ever...
November 23, 2009
2001 GMC Sonoma SLS 4.3L Misfire, MIL Lamp on VIN: 1GTCS14W01
P0304: Cylinder 4 Misfire Detected. This GMC shows that there is a misfire on cylinder 4 as soon as the truck is raised off idle. The misfire counter counts rapidly on cylinder 4 above about 1400 rpm, when the engine speed is held steady. It does not count when idling or when revving quickly and...
November 24, 2009
2000 Ford Taurus SE 4-Valve 3.0L Misfire, MIL Lamp on VIN: 1FAFP56SXY
P0304: 4 misfire. Hello This Taurus runs good 90% of the tine. Then it will develop a severe lack of power, as it runs on 3 cylinders. It runs on only 1,2,and3 when it messes up. The engine light will flash, suddenly it straightens out and runs great. It has COP, and when it w...
November 30, 2009