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P0304 Diagnostic Trouble Code Discussion for January 2011

Cylinder 4 Misfire Detected


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Trouble Ticket Help Requests for DTC P0304
Help Request Posted
2008 Mazda 6 S 3.0L Misfire, MIL Lamp on VIN: 1YVHP80D48
P0304: Cyl 4 misfire. Vehicle came in with CEL on. Code says misfire on cyl 4. Vehicle ran fine on test drives. Freeze frame showed misfire happened at 4500 rpm, ECT 70 degrees Celcius, 95 kph, 99.22 load. Swapped coils and plugs. Test drive: OK. Days later vehicle came back with s...
January 06, 2011
1999 Ford Ranger XLT 4.0L Misfire VIN: 1FTZR15X8X
P0304: Misfire 4 cylinder. Heads up ford techs, need some info. Truck came into the shop customer complaining about the #4 spark plug fowling out after 1000 miles everytime he replaces it. customer has replaced himself the plugs(motorcraft), wires and coil pack. the plug is not fuel fow...
January 11, 2011
2002 Isuzu Axiom 3.5L Flashing MIL/no miss VIN: 4S2CE58X22
P0304: Cylinder 4 Misfire Detected. ... others benefit. We replaced the spark plugs for maintenance and ever since then, sometimes while accelerating the check engine light would flash. When you go to idle, the chk eng light would stop flashing and go out, it would not remain lit. Truck runs fin...
January 20, 2011
2005 Ford F-150 XL 5.4L Misfire, MIL Lamp on VIN: 1FTVX12585
P0304: misfire 4 cylinder. Vehicle came in with misfire code po304 and obvious misfire. Due to problems with plugs on this 3 valve engine, checked coil output (good spark) but swapped with another to try and see if misfire moved. No change. Customer said plugs original, but when we went...
January 24, 2011
2008 Mazda 6 S 3.0L Misfire, MIL Lamp on VIN: 1YVHP80D48
P0304: Cyl 4 misfire. Vehicle came in with CEL on. Code says misfire on cyl 4. Vehicle ran fine on test drives. Freeze frame showed misfire happened at 4500 rpm, ECT 70 degrees Celcius, 95 kph, 99.22 load. Swapped coils and plugs. Test drive: OK. Days later vehicle came back with s...
January 25, 2011
2001 Honda Accord EX 2.3L Poor Idle Quality VIN: 1HGCG66851
P0304: Cylinder 4 Misfire Detected. 2001 Honda presented with leaking balance shaft seal found that the seal scored the pump housing replaced oil pump timing belt and seals; vehicle towed back in with broken cam clean break at pulley to cam mating, obtained a used cam and installed found that #2...
January 28, 2011
2003 Saab 9-5 Linear 2.3L MIL Lamp on VIN: YS3EB49E03
P0304: Numb 4 cyld. wtf... we got a used ecu from a wrecker and programed it. idle seems worse. misfire codes set at idle as before thanks in advance to anyone who's seen this or can give us a direction to blindly follow!?
January 28, 2011
1999 Honda Accord LX 3.0L Misfire VIN: 1HGCG1657X
P0304: Cylinder 4 Misfire Detected. This car has a constant misfire, cylinder 2 and 5 set codes right away, but after a while all cylinders set misfire codes. It is driving me nuts!! The fuel pressure and volume are both good. The Egr system is working fine. I don't know what else would cause a ...
January 31, 2011
2008 Mazda 6 S 3.0L Misfire, MIL Lamp on VIN: 1YVHP80D48
P0304: Cyl 4 misfire. Vehicle came in with CEL on. Code says misfire on cyl 4. Vehicle ran fine on test drives. Freeze frame showed misfire happened at 4500 rpm, ECT 70 degrees Celcius, 95 kph, 99.22 load. Swapped coils and plugs. Test drive: OK. Days later vehicle came back with s...
January 06, 2011
1999 Ford Ranger XLT 4.0L Misfire VIN: 1FTZR15X8X
P0304: Misfire 4 cylinder. Heads up ford techs, need some info. Truck came into the shop customer complaining about the #4 spark plug fowling out after 1000 miles everytime he replaces it. customer has replaced himself the plugs(motorcraft), wires and coil pack. the plug is not fuel fow...
January 11, 2011
2002 Isuzu Axiom 3.5L Flashing MIL/no miss VIN: 4S2CE58X22
P0304: Cylinder 4 Misfire Detected. ... others benefit. We replaced the spark plugs for maintenance and ever since then, sometimes while accelerating the check engine light would flash. When you go to idle, the chk eng light would stop flashing and go out, it would not remain lit. Truck runs fin...
January 20, 2011
2005 Ford F-150 XL 5.4L Misfire, MIL Lamp on VIN: 1FTVX12585
P0304: misfire 4 cylinder. Vehicle came in with misfire code po304 and obvious misfire. Due to problems with plugs on this 3 valve engine, checked coil output (good spark) but swapped with another to try and see if misfire moved. No change. Customer said plugs original, but when we went...
January 24, 2011
2008 Mazda 6 S 3.0L Misfire, MIL Lamp on VIN: 1YVHP80D48
P0304: Cyl 4 misfire. Vehicle came in with CEL on. Code says misfire on cyl 4. Vehicle ran fine on test drives. Freeze frame showed misfire happened at 4500 rpm, ECT 70 degrees Celcius, 95 kph, 99.22 load. Swapped coils and plugs. Test drive: OK. Days later vehicle came back with s...
January 25, 2011
2001 Honda Accord EX 2.3L Poor Idle Quality VIN: 1HGCG66851
P0304: Cylinder 4 Misfire Detected. 2001 Honda presented with leaking balance shaft seal found that the seal scored the pump housing replaced oil pump timing belt and seals; vehicle towed back in with broken cam clean break at pulley to cam mating, obtained a used cam and installed found that #2...
January 28, 2011
2003 Saab 9-5 Linear 2.3L MIL Lamp on VIN: YS3EB49E03
P0304: Numb 4 cyld. wtf... we got a used ecu from a wrecker and programed it. idle seems worse. misfire codes set at idle as before thanks in advance to anyone who's seen this or can give us a direction to blindly follow!?
January 28, 2011
1999 Honda Accord LX 3.0L Misfire VIN: 1HGCG1657X
P0304: Cylinder 4 Misfire Detected. This car has a constant misfire, cylinder 2 and 5 set codes right away, but after a while all cylinders set misfire codes. It is driving me nuts!! The fuel pressure and volume are both good. The Egr system is working fine. I don't know what else would cause a ...
January 31, 2011