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P0304 Diagnostic Trouble Code Discussion for January 2014

Cylinder 4 Misfire Detected


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Trouble Ticket Help Requests for DTC P0304
Help Request Posted
2006 Kia Optima LX 2.4L Misfire, MIL Lamp on VIN: KNAGE123X6
P0304: Cylinder 4 Misfire Detected. Hello everyone and thanks for taking the time to look at this. Got a very strange one here. We got this vehicle at 133000 miles with a rod knock, very minor. Removed and rebuilt engine. Installed engine and everything was perfect. Vehicle ran great, no check e...
January 08, 2014
2007 Mercedes-Benz C230 Sport 2.5L Excessive Emissions, Misfire VIN: WDBRF52H97
P0304: Misfire 4. Customer first came in with an issue relating to cold starting. The vehicle would have a hard time starting. It would run very rich once it did start. Once the car warms ups it seems to run fine. I initially looked at fuel pressure and found this to be ok arou...
January 09, 2014
2006 Kia Optima LX 2.4L Misfire, MIL Lamp on VIN: KNAGE123X6
P0304: Cylinder 4 Misfire Detected. Hello everyone and thanks for taking the time to look at this. Got a very strange one here. We got this vehicle at 133000 miles with a rod knock, very minor. Removed and rebuilt engine. Installed engine and everything was perfect. Vehicle ran great, no check e...
January 12, 2014
2005 GMC Sierra 2500 HD SLE 6.6L MIL Lamp on, Fuel Rattle VIN: 1GTHK23245
P0304: Cylinder 4 Misfire Detected. ... Help Truck came in fuel smoking and a number four cyinder misfire code, tested injector and found it to be bad. Also had a MAF sensor code P0101 found bad connector pin. Replaced MAF and connector with OE parts. Replaced number 4 injector, ran truck no smo...
January 13, 2014
1997 Volkswagen Jetta GL 2.0L Stall VIN: 3VWWB81HXV
P0304: cyl 4 misfire. hello everyone this vehicle has a very intermitten stall from a stop like a traffic light then when taking off it will stall, then may be an extended or labored restart. i have driven this vehicle for a week to and from work without any problems. cust has driv...
January 14, 2014
2005 Audi S4 4.2L Poor Idle Quality, Misfire, MIL Lamp on VIN: WUARL48HX5
P0304: Cylinder 4 misfire. Car came in on wrecker for no start. Checked and found bad fuel pump. Installed new pump and filter. Car started right up. Was missing terribly with check engine light on.Scanned and retrieved misfire faults.Checked spark plugs and coils , were good. Customer ...
January 16, 2014
2005 Audi S4 4.2L Hesitation, Cuts out, Misfire VIN: WAUPL68E95
P0304: cylinder 4 misfire. We have this 05 S4 standard. Codes P0300, 304, 306 and 308 continue to be set for very harsh misfire. These codes come back every time. Idles and starts fine, hot or cold. First start of day chains rattle for a second or so. No roughness at idle, or no load pa...
January 17, 2014
2007 Toyota Camry XLE 3.5L Misfire VIN: 4T1BK46KX7
P0304: Cylinder 4 Misfire Detected. Car came in running badly with cylinder 4 misfire. We removed plenum & immediately saw we had a rodent infestation. After cleaning out the nest we found that the wires to the fuel injector on cyl. 4 were chewed. We repaired wires, same symptom, we switched...
January 20, 2014
2004 Isuzu Rodeo S 3.5L Poor Idle Quality, Hesitation, Surge, Cuts out, Stall, Misfire, MIL Lamp on VIN: 4S2DM58Y44
P0304: Cylinder 4 Misfire Detected. This is more of an informative post than a need for help. This vehicle has been to several shops with just about every sensor either replaced or swapped in the attempt to repair fault. All symptoms where intermittent. Miss fires at start up and or during drivi...
January 22, 2014
2004 Subaru Forester XT 2.5L Misfire, MIL Lamp on VIN: JF1SG69604
P0304: Cylinder 4 Misfire Detected. ... Forester DOHC Turbo here that came in last week for a minor service. We noted that engine needs timing belt which we finished yesterday. Engine ran fine before replacing timing belt. Got timing belt, idler pulleys and water pump all replaced. (Drivers side...
January 23, 2014
2002 Ford Escape XLT 3.0L No Start, Poor Idle Quality, Hesitation, Cuts out, Stall, Misfire, MIL Lamp on
P0304: Cyl 4 misfire. Hello everybody and thank you in advance for your help and guidance. A customer just bought their 02 Escape recently for their son. They brought it to me to get the random misfire and poor idle quality taken care of. The customer put some fuel inj. cleaner in ...
January 24, 2014
2000 Honda Accord EX 3.0L Poor Idle Quality, Misfire, MIL Lamp on VIN: 1HGCG2252Y
P0304: Cylinder 4 Misfire Detected. The MIL is flashing during idle and cruise. There's also a code P0306, but there wasn't room to list all the codes in the entry form for this help request. All cylinders have good compression, but spark plugs look partly sooty, as if sometimes they are gas fou...
January 24, 2014
2008 Subaru Impreza 2.5i 2.5L Poor Idle Quality, Stall, Misfire, MIL Lamp on VIN: JF1GH61698
P0304: b -. Really stumped on this one. Vehicle idles very poor and will die at idle in gear. After stalling it hard starts and will not fire unless the throttle is held down. Here's a list of what I've checked so far: -MAF - tried swaping a new one in with the same resu...
January 24, 2014
2000 Honda Accord EX 3.0L Poor Idle Quality, Misfire, MIL Lamp on VIN: 1HGCG2252Y
P0304: Cylinder 4 Misfire Detected. The MIL is flashing during idle and cruise. There's also a code P0306, but there wasn't room to list all the codes in the entry form for this help request. All cylinders have good compression, but spark plugs look partly sooty, as if sometimes they are gas fou...
January 26, 2014
2000 Honda Accord LX 3.0L No Start, Poor Idle Quality, Misfire, MIL Lamp on VIN: 1HGCG1641Y
P0304: Cylinder 4 Misfire Detected. This Accord will not start hot after a hot soak. The Main relay has been removed and inspected on the circuit board. The ignition system hasn't been checked past the fact that we have good spark when the problem is there. When we cracked the fuel line we get v...
January 27, 2014
2000 Pontiac Grand Prix GT 3.8L Misfire, MIL Lamp on VIN: 1G2WP52K5Y
P0304: misfire on 4. Hi everybody looking for help on this one we did cylinder heads on this for a #4 burnt exhaust valve and we put it back together and it now misses only at idle on #4 cylinder we have swapped injectors, coils, wires, plugs, and put a ignition control module on ...
January 29, 2014
2002 Audi A6 Quattro 3.0L Excessive Emissions, Poor Idle Quality, Hesitation, Surge, Cuts out, Stall, Misfire, Poor Fuel Economy, MIL Lamp on VIN: WAULT64B92
P0304: misfire cyl 4. Customer bought this car a 2 weeks ago. The engine light came on and it lost power on Saturday, about 9 days after he bought it. When it starts, it misfires bad, runs terrible , has no power, wont accelerate, and backfires through the intake. I have no service...
January 30, 2014
2006 Volkswagen Touareg 3.2L Excessive Emissions, Poor Idle Quality, Hesitation, Stall, Misfire, MIL Lamp on VIN: WVGZG77L66
P0304: Cyl 4 mis. Vehicle was drove in and dropped off for poor running, stall and mil on. Notice "related repair history". Vehicle would not start when brought in. Suspected fouled plugs. Have experience with vw and have the VCDS for them. But do not have much experien...
January 30, 2014
2006 Kia Optima LX 2.4L Misfire, MIL Lamp on VIN: KNAGE123X6
P0304: Cylinder 4 Misfire Detected. Hello everyone and thanks for taking the time to look at this. Got a very strange one here. We got this vehicle at 133000 miles with a rod knock, very minor. Removed and rebuilt engine. Installed engine and everything was perfect. Vehicle ran great, no check e...
January 08, 2014
2007 Mercedes-Benz C230 Sport 2.5L Excessive Emissions, Misfire VIN: WDBRF52H97
P0304: Misfire 4. Customer first came in with an issue relating to cold starting. The vehicle would have a hard time starting. It would run very rich once it did start. Once the car warms ups it seems to run fine. I initially looked at fuel pressure and found this to be ok arou...
January 09, 2014
2006 Kia Optima LX 2.4L Misfire, MIL Lamp on VIN: KNAGE123X6
P0304: Cylinder 4 Misfire Detected. Hello everyone and thanks for taking the time to look at this. Got a very strange one here. We got this vehicle at 133000 miles with a rod knock, very minor. Removed and rebuilt engine. Installed engine and everything was perfect. Vehicle ran great, no check e...
January 12, 2014
2005 GMC Sierra 2500 HD SLE 6.6L MIL Lamp on, Fuel Rattle VIN: 1GTHK23245
P0304: Cylinder 4 Misfire Detected. ... Help Truck came in fuel smoking and a number four cyinder misfire code, tested injector and found it to be bad. Also had a MAF sensor code P0101 found bad connector pin. Replaced MAF and connector with OE parts. Replaced number 4 injector, ran truck no smo...
January 13, 2014
1997 Volkswagen Jetta GL 2.0L Stall VIN: 3VWWB81HXV
P0304: cyl 4 misfire. hello everyone this vehicle has a very intermitten stall from a stop like a traffic light then when taking off it will stall, then may be an extended or labored restart. i have driven this vehicle for a week to and from work without any problems. cust has driv...
January 14, 2014
2005 Audi S4 4.2L Poor Idle Quality, Misfire, MIL Lamp on VIN: WUARL48HX5
P0304: Cylinder 4 misfire. Car came in on wrecker for no start. Checked and found bad fuel pump. Installed new pump and filter. Car started right up. Was missing terribly with check engine light on.Scanned and retrieved misfire faults.Checked spark plugs and coils , were good. Customer ...
January 16, 2014
2005 Audi S4 4.2L Hesitation, Cuts out, Misfire VIN: WAUPL68E95
P0304: cylinder 4 misfire. We have this 05 S4 standard. Codes P0300, 304, 306 and 308 continue to be set for very harsh misfire. These codes come back every time. Idles and starts fine, hot or cold. First start of day chains rattle for a second or so. No roughness at idle, or no load pa...
January 17, 2014
2007 Toyota Camry XLE 3.5L Misfire VIN: 4T1BK46KX7
P0304: Cylinder 4 Misfire Detected. Car came in running badly with cylinder 4 misfire. We removed plenum & immediately saw we had a rodent infestation. After cleaning out the nest we found that the wires to the fuel injector on cyl. 4 were chewed. We repaired wires, same symptom, we switched...
January 20, 2014
2004 Isuzu Rodeo S 3.5L Poor Idle Quality, Hesitation, Surge, Cuts out, Stall, Misfire, MIL Lamp on VIN: 4S2DM58Y44
P0304: Cylinder 4 Misfire Detected. This is more of an informative post than a need for help. This vehicle has been to several shops with just about every sensor either replaced or swapped in the attempt to repair fault. All symptoms where intermittent. Miss fires at start up and or during drivi...
January 22, 2014
2004 Subaru Forester XT 2.5L Misfire, MIL Lamp on VIN: JF1SG69604
P0304: Cylinder 4 Misfire Detected. ... Forester DOHC Turbo here that came in last week for a minor service. We noted that engine needs timing belt which we finished yesterday. Engine ran fine before replacing timing belt. Got timing belt, idler pulleys and water pump all replaced. (Drivers side...
January 23, 2014
2002 Ford Escape XLT 3.0L No Start, Poor Idle Quality, Hesitation, Cuts out, Stall, Misfire, MIL Lamp on
P0304: Cyl 4 misfire. Hello everybody and thank you in advance for your help and guidance. A customer just bought their 02 Escape recently for their son. They brought it to me to get the random misfire and poor idle quality taken care of. The customer put some fuel inj. cleaner in ...
January 24, 2014
2000 Honda Accord EX 3.0L Poor Idle Quality, Misfire, MIL Lamp on VIN: 1HGCG2252Y
P0304: Cylinder 4 Misfire Detected. The MIL is flashing during idle and cruise. There's also a code P0306, but there wasn't room to list all the codes in the entry form for this help request. All cylinders have good compression, but spark plugs look partly sooty, as if sometimes they are gas fou...
January 24, 2014
2008 Subaru Impreza 2.5i 2.5L Poor Idle Quality, Stall, Misfire, MIL Lamp on VIN: JF1GH61698
P0304: b -. Really stumped on this one. Vehicle idles very poor and will die at idle in gear. After stalling it hard starts and will not fire unless the throttle is held down. Here's a list of what I've checked so far: -MAF - tried swaping a new one in with the same resu...
January 24, 2014
2000 Honda Accord EX 3.0L Poor Idle Quality, Misfire, MIL Lamp on VIN: 1HGCG2252Y
P0304: Cylinder 4 Misfire Detected. The MIL is flashing during idle and cruise. There's also a code P0306, but there wasn't room to list all the codes in the entry form for this help request. All cylinders have good compression, but spark plugs look partly sooty, as if sometimes they are gas fou...
January 26, 2014
2000 Honda Accord LX 3.0L No Start, Poor Idle Quality, Misfire, MIL Lamp on VIN: 1HGCG1641Y
P0304: Cylinder 4 Misfire Detected. This Accord will not start hot after a hot soak. The Main relay has been removed and inspected on the circuit board. The ignition system hasn't been checked past the fact that we have good spark when the problem is there. When we cracked the fuel line we get v...
January 27, 2014
2000 Pontiac Grand Prix GT 3.8L Misfire, MIL Lamp on VIN: 1G2WP52K5Y
P0304: misfire on 4. Hi everybody looking for help on this one we did cylinder heads on this for a #4 burnt exhaust valve and we put it back together and it now misses only at idle on #4 cylinder we have swapped injectors, coils, wires, plugs, and put a ignition control module on ...
January 29, 2014
2002 Audi A6 Quattro 3.0L Excessive Emissions, Poor Idle Quality, Hesitation, Surge, Cuts out, Stall, Misfire, Poor Fuel Economy, MIL Lamp on VIN: WAULT64B92
P0304: misfire cyl 4. Customer bought this car a 2 weeks ago. The engine light came on and it lost power on Saturday, about 9 days after he bought it. When it starts, it misfires bad, runs terrible , has no power, wont accelerate, and backfires through the intake. I have no service...
January 30, 2014
2006 Volkswagen Touareg 3.2L Excessive Emissions, Poor Idle Quality, Hesitation, Stall, Misfire, MIL Lamp on VIN: WVGZG77L66
P0304: Cyl 4 mis. Vehicle was drove in and dropped off for poor running, stall and mil on. Notice "related repair history". Vehicle would not start when brought in. Suspected fouled plugs. Have experience with vw and have the VCDS for them. But do not have much experien...
January 30, 2014
2006 Kia Optima LX 2.4L Misfire, MIL Lamp on VIN: KNAGE123X6
P0304: Cylinder 4 Misfire Detected. Hello everyone and thanks for taking the time to look at this. Got a very strange one here. We got this vehicle at 133000 miles with a rod knock, very minor. Removed and rebuilt engine. Installed engine and everything was perfect. Vehicle ran great, no check e...
January 08, 2014
2007 Mercedes-Benz C230 Sport 2.5L Excessive Emissions, Misfire VIN: WDBRF52H97
P0304: Misfire 4. Customer first came in with an issue relating to cold starting. The vehicle would have a hard time starting. It would run very rich once it did start. Once the car warms ups it seems to run fine. I initially looked at fuel pressure and found this to be ok arou...
January 09, 2014
2006 Kia Optima LX 2.4L Misfire, MIL Lamp on VIN: KNAGE123X6
P0304: Cylinder 4 Misfire Detected. Hello everyone and thanks for taking the time to look at this. Got a very strange one here. We got this vehicle at 133000 miles with a rod knock, very minor. Removed and rebuilt engine. Installed engine and everything was perfect. Vehicle ran great, no check e...
January 12, 2014
2005 GMC Sierra 2500 HD SLE 6.6L MIL Lamp on, Fuel Rattle VIN: 1GTHK23245
P0304: Cylinder 4 Misfire Detected. ... Help Truck came in fuel smoking and a number four cyinder misfire code, tested injector and found it to be bad. Also had a MAF sensor code P0101 found bad connector pin. Replaced MAF and connector with OE parts. Replaced number 4 injector, ran truck no smo...
January 13, 2014
1997 Volkswagen Jetta GL 2.0L Stall VIN: 3VWWB81HXV
P0304: cyl 4 misfire. hello everyone this vehicle has a very intermitten stall from a stop like a traffic light then when taking off it will stall, then may be an extended or labored restart. i have driven this vehicle for a week to and from work without any problems. cust has driv...
January 14, 2014
2005 Audi S4 4.2L Poor Idle Quality, Misfire, MIL Lamp on VIN: WUARL48HX5
P0304: Cylinder 4 misfire. Car came in on wrecker for no start. Checked and found bad fuel pump. Installed new pump and filter. Car started right up. Was missing terribly with check engine light on.Scanned and retrieved misfire faults.Checked spark plugs and coils , were good. Customer ...
January 16, 2014
2005 Audi S4 4.2L Hesitation, Cuts out, Misfire VIN: WAUPL68E95
P0304: cylinder 4 misfire. We have this 05 S4 standard. Codes P0300, 304, 306 and 308 continue to be set for very harsh misfire. These codes come back every time. Idles and starts fine, hot or cold. First start of day chains rattle for a second or so. No roughness at idle, or no load pa...
January 17, 2014
2007 Toyota Camry XLE 3.5L Misfire VIN: 4T1BK46KX7
P0304: Cylinder 4 Misfire Detected. Car came in running badly with cylinder 4 misfire. We removed plenum & immediately saw we had a rodent infestation. After cleaning out the nest we found that the wires to the fuel injector on cyl. 4 were chewed. We repaired wires, same symptom, we switched...
January 20, 2014
2004 Isuzu Rodeo S 3.5L Poor Idle Quality, Hesitation, Surge, Cuts out, Stall, Misfire, MIL Lamp on VIN: 4S2DM58Y44
P0304: Cylinder 4 Misfire Detected. This is more of an informative post than a need for help. This vehicle has been to several shops with just about every sensor either replaced or swapped in the attempt to repair fault. All symptoms where intermittent. Miss fires at start up and or during drivi...
January 22, 2014
2004 Subaru Forester XT 2.5L Misfire, MIL Lamp on VIN: JF1SG69604
P0304: Cylinder 4 Misfire Detected. ... Forester DOHC Turbo here that came in last week for a minor service. We noted that engine needs timing belt which we finished yesterday. Engine ran fine before replacing timing belt. Got timing belt, idler pulleys and water pump all replaced. (Drivers side...
January 23, 2014
2002 Ford Escape XLT 3.0L No Start, Poor Idle Quality, Hesitation, Cuts out, Stall, Misfire, MIL Lamp on
P0304: Cyl 4 misfire. Hello everybody and thank you in advance for your help and guidance. A customer just bought their 02 Escape recently for their son. They brought it to me to get the random misfire and poor idle quality taken care of. The customer put some fuel inj. cleaner in ...
January 24, 2014
2000 Honda Accord EX 3.0L Poor Idle Quality, Misfire, MIL Lamp on VIN: 1HGCG2252Y
P0304: Cylinder 4 Misfire Detected. The MIL is flashing during idle and cruise. There's also a code P0306, but there wasn't room to list all the codes in the entry form for this help request. All cylinders have good compression, but spark plugs look partly sooty, as if sometimes they are gas fou...
January 24, 2014
2008 Subaru Impreza 2.5i 2.5L Poor Idle Quality, Stall, Misfire, MIL Lamp on VIN: JF1GH61698
P0304: b -. Really stumped on this one. Vehicle idles very poor and will die at idle in gear. After stalling it hard starts and will not fire unless the throttle is held down. Here's a list of what I've checked so far: -MAF - tried swaping a new one in with the same resu...
January 24, 2014
2000 Honda Accord EX 3.0L Poor Idle Quality, Misfire, MIL Lamp on VIN: 1HGCG2252Y
P0304: Cylinder 4 Misfire Detected. The MIL is flashing during idle and cruise. There's also a code P0306, but there wasn't room to list all the codes in the entry form for this help request. All cylinders have good compression, but spark plugs look partly sooty, as if sometimes they are gas fou...
January 26, 2014
2000 Honda Accord LX 3.0L No Start, Poor Idle Quality, Misfire, MIL Lamp on VIN: 1HGCG1641Y
P0304: Cylinder 4 Misfire Detected. This Accord will not start hot after a hot soak. The Main relay has been removed and inspected on the circuit board. The ignition system hasn't been checked past the fact that we have good spark when the problem is there. When we cracked the fuel line we get v...
January 27, 2014
2000 Pontiac Grand Prix GT 3.8L Misfire, MIL Lamp on VIN: 1G2WP52K5Y
P0304: misfire on 4. Hi everybody looking for help on this one we did cylinder heads on this for a #4 burnt exhaust valve and we put it back together and it now misses only at idle on #4 cylinder we have swapped injectors, coils, wires, plugs, and put a ignition control module on ...
January 29, 2014
2002 Audi A6 Quattro 3.0L Excessive Emissions, Poor Idle Quality, Hesitation, Surge, Cuts out, Stall, Misfire, Poor Fuel Economy, MIL Lamp on VIN: WAULT64B92
P0304: misfire cyl 4. Customer bought this car a 2 weeks ago. The engine light came on and it lost power on Saturday, about 9 days after he bought it. When it starts, it misfires bad, runs terrible , has no power, wont accelerate, and backfires through the intake. I have no service...
January 30, 2014
2006 Volkswagen Touareg 3.2L Excessive Emissions, Poor Idle Quality, Hesitation, Stall, Misfire, MIL Lamp on VIN: WVGZG77L66
P0304: Cyl 4 mis. Vehicle was drove in and dropped off for poor running, stall and mil on. Notice "related repair history". Vehicle would not start when brought in. Suspected fouled plugs. Have experience with vw and have the VCDS for them. But do not have much experien...
January 30, 2014