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P0304 Diagnostic Trouble Code Discussion for March 2013

Cylinder 4 Misfire Detected


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Trouble Ticket Help Requests for DTC P0304
Help Request Posted
2005 Ford Explorer XLT 4.0L Poor Idle Quality, Misfire, MIL Lamp on VIN: 1FMZU73K75
P0304: cylinder 4 misfire. 2005 Explorer 4.0 came to us after being at another shop. Came in with rough idle and misfires. The other shop replaced plugs wires and egr valve and intake gaskets. We checked plugs and found they used autolites so we replaced with motorcraft no change. We re...
March 04, 2013
2005 Ford F-250 Super Duty Lariat 5.4L Poor Idle Quality, Cuts out, Stall, MIL Lamp on VIN: 1FTSW21565
P0304: Fault Cylinder 4 Misfire Detected. ... f-250 with 5.4l 3 valve engine with 200,000 miles. Truck runs very rough at idle then will smooth out and run fine. road test and truck will barely pull itself. never dies but has no power then will go for a while (runs poorly but will run). cylinder contr...
March 06, 2013
2005 Ford Explorer XLT 4.0L Poor Idle Quality, Misfire, MIL Lamp on VIN: 1FMZU73K75
P0304: cylinder 4 misfire. 2005 Explorer 4.0 came to us after being at another shop. Came in with rough idle and misfires. The other shop replaced plugs wires and egr valve and intake gaskets. We checked plugs and found they used autolites so we replaced with motorcraft no change. We re...
March 06, 2013
2007 Chevrolet Aveo LS 1.6L Misfire VIN: KL1TD65657
P0304: Cylinder 4 Misfire Detected. So this Aveo is a used car on the lot. Didn't run good when we first got it but was low on fuel and then ran fine. So it sat on the lot for a while then sold it but noticed coolant leak before it got picked up. So we changed the timing belt and water pump. So ...
March 07, 2013
1998 GMC K3500 Sierra SL 7.4L Poor Idle Quality, Cuts out, Misfire VIN: 1GDHK33J1W
P0304: Cylinder 4 Misfire Detected. This vehicle is from one of my car lot accounts. Came to us with very rough idle, very low on power. Found #4 injector to be incorrect injector,replaced it along with a new fuel rail(hold down clips broken)still multiple misfires intermittently, always #4, and...
March 07, 2013
2006 Ford Fusion SEL 3.0L Misfire, MIL Lamp on VIN: 3FAFP08186
P0304: No. 4 misfire. Vehicle came in with random misfire, and codes for front bank misfires. 4, 5, 6. scanned computer and observed bank 2 downstream O2 sensor flatlined. Installed new sensor and ran self test with normal operation. Vehicle returned with same codes and O2 flatline...
March 13, 2013
2001 Subaru Outback VDC 3.0L Misfire VIN: 4S3BH89661
P0304: Cylinder 4 Misfire Detected. hi there i am on working on this 01 subaru 3.0 liter that sets misfire codes for cylinder 4 and 6.checked vacuum 18-20 inhg did noticed left side bank goes rich was it goes to close loop a/f sensor reads .84 lambda and fuel trims area at -22 total fuel trims t...
March 19, 2013
2006 Ford Fusion SEL 3.0L Misfire, MIL Lamp on VIN: 3FAFP08186
P0304: No. 4 misfire. Vehicle came in with random misfire, and codes for front bank misfires. 4, 5, 6. scanned computer and observed bank 2 downstream O2 sensor flatlined. Installed new sensor and ran self test with normal operation. Vehicle returned with same codes and O2 flatline...
March 20, 2013
2007 Chevrolet Aveo LS 1.6L Misfire VIN: KL1TD65657
P0304: Cylinder 4 Misfire Detected. So this Aveo is a used car on the lot. Didn't run good when we first got it but was low on fuel and then ran fine. So it sat on the lot for a while then sold it but noticed coolant leak before it got picked up. So we changed the timing belt and water pump. So ...
March 25, 2013
2003 Land Rover Discovery S 4.6L Misfire VIN: SALTL16423
P0304: Cylinder 4 miss fire detected. ... originally oil leaks out of the oil pan, head gasket, and timing cove gasket. Cylinder heads were removed and the were faced at machine shop, valves were tested for leakage but were not leaking. (service writer decided not to have the valve seals changed e...
March 27, 2013
2007 Audi A3 2.0L Misfire VIN: WAUHF78PX7
P0304: . In past 1 year and 4 mos this vehicle had misfire issues. Initially we changed all 4 plugs and coils with OEM as it is common. Did air filter and mass air cleaning. Seemed to clear up. Then came back running badly a month later. We found bad High Pressure Fuel...
March 28, 2013
2005 Ford Explorer XLT 4.0L Poor Idle Quality, Misfire, MIL Lamp on VIN: 1FMZU73K75
P0304: cylinder 4 misfire. 2005 Explorer 4.0 came to us after being at another shop. Came in with rough idle and misfires. The other shop replaced plugs wires and egr valve and intake gaskets. We checked plugs and found they used autolites so we replaced with motorcraft no change. We re...
March 04, 2013
2005 Ford F-250 Super Duty Lariat 5.4L Poor Idle Quality, Cuts out, Stall, MIL Lamp on VIN: 1FTSW21565
P0304: Fault Cylinder 4 Misfire Detected. ... f-250 with 5.4l 3 valve engine with 200,000 miles. Truck runs very rough at idle then will smooth out and run fine. road test and truck will barely pull itself. never dies but has no power then will go for a while (runs poorly but will run). cylinder contr...
March 06, 2013
2005 Ford Explorer XLT 4.0L Poor Idle Quality, Misfire, MIL Lamp on VIN: 1FMZU73K75
P0304: cylinder 4 misfire. 2005 Explorer 4.0 came to us after being at another shop. Came in with rough idle and misfires. The other shop replaced plugs wires and egr valve and intake gaskets. We checked plugs and found they used autolites so we replaced with motorcraft no change. We re...
March 06, 2013
2007 Chevrolet Aveo LS 1.6L Misfire VIN: KL1TD65657
P0304: Cylinder 4 Misfire Detected. So this Aveo is a used car on the lot. Didn't run good when we first got it but was low on fuel and then ran fine. So it sat on the lot for a while then sold it but noticed coolant leak before it got picked up. So we changed the timing belt and water pump. So ...
March 07, 2013
1998 GMC K3500 Sierra SL 7.4L Poor Idle Quality, Cuts out, Misfire VIN: 1GDHK33J1W
P0304: Cylinder 4 Misfire Detected. This vehicle is from one of my car lot accounts. Came to us with very rough idle, very low on power. Found #4 injector to be incorrect injector,replaced it along with a new fuel rail(hold down clips broken)still multiple misfires intermittently, always #4, and...
March 07, 2013
2006 Ford Fusion SEL 3.0L Misfire, MIL Lamp on VIN: 3FAFP08186
P0304: No. 4 misfire. Vehicle came in with random misfire, and codes for front bank misfires. 4, 5, 6. scanned computer and observed bank 2 downstream O2 sensor flatlined. Installed new sensor and ran self test with normal operation. Vehicle returned with same codes and O2 flatline...
March 13, 2013
2001 Subaru Outback VDC 3.0L Misfire VIN: 4S3BH89661
P0304: Cylinder 4 Misfire Detected. hi there i am on working on this 01 subaru 3.0 liter that sets misfire codes for cylinder 4 and 6.checked vacuum 18-20 inhg did noticed left side bank goes rich was it goes to close loop a/f sensor reads .84 lambda and fuel trims area at -22 total fuel trims t...
March 19, 2013
2006 Ford Fusion SEL 3.0L Misfire, MIL Lamp on VIN: 3FAFP08186
P0304: No. 4 misfire. Vehicle came in with random misfire, and codes for front bank misfires. 4, 5, 6. scanned computer and observed bank 2 downstream O2 sensor flatlined. Installed new sensor and ran self test with normal operation. Vehicle returned with same codes and O2 flatline...
March 20, 2013
2007 Chevrolet Aveo LS 1.6L Misfire VIN: KL1TD65657
P0304: Cylinder 4 Misfire Detected. So this Aveo is a used car on the lot. Didn't run good when we first got it but was low on fuel and then ran fine. So it sat on the lot for a while then sold it but noticed coolant leak before it got picked up. So we changed the timing belt and water pump. So ...
March 25, 2013
2003 Land Rover Discovery S 4.6L Misfire VIN: SALTL16423
P0304: Cylinder 4 miss fire detected. ... originally oil leaks out of the oil pan, head gasket, and timing cove gasket. Cylinder heads were removed and the were faced at machine shop, valves were tested for leakage but were not leaking. (service writer decided not to have the valve seals changed e...
March 27, 2013
2007 Audi A3 2.0L Misfire VIN: WAUHF78PX7
P0304: . In past 1 year and 4 mos this vehicle had misfire issues. Initially we changed all 4 plugs and coils with OEM as it is common. Did air filter and mass air cleaning. Seemed to clear up. Then came back running badly a month later. We found bad High Pressure Fuel...
March 28, 2013