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P0304 Diagnostic Trouble Code Discussion for March 2007

Cylinder 4 Misfire Detected


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Trouble Ticket Help Requests for DTC P0304
Help Request Posted
2000 Honda CR-V LX 2.0L Poor Idle Quality, Cuts out, Misfire VIN: JHLRD28461
P0304: Cylinder 4 Misfire Detected. vehicle presents when cold runs extremly rough at idle/ lean once starts to warm will idle but poorly and is drivable.map sensor at idle reads approx 1.4-1.5 volts with a vac reading of approx 14 inches... If it had one i would say EGR is stuck open only codes...
March 02, 2007
1996 Ford Explorer Eddie Bauer 4.0L Poor Idle Quality, Misfire VIN: 1FMDU34X9T
P0304: 4 misfire. Hi all Got this explorer yesterday customer replaced plugs-wires-coil-fuel filter for this miss, still there. dead miss #4 I check codes, po304 active but #2 failed also in mode6, check vac leaks,firing order,compression, fuel pressure,spark all ok, slight int...
March 03, 2007
2002 Jaguar Vanden Plas 4.0L Poor Idle Quality, Misfire VIN: SAJDA24C82
P0304: miss fire cyl 4. HELLO GROUP: I need some help on this car, no matter what i do, it keeps on miss firing. Before injector flush it was showing miss fire cyl 1 2 and 4, now cyl 7 and 8. I've checked crank angle sensor wave form , it looked good. Inspected flywheel for warpage a...
March 05, 2007
2000 Jeep Cherokee Sport 4.0L Poor Idle Quality, f trim / O2 heater VIN: 1J4FF48S4Y
P0304: Cylinder 4 Misfire Detected. NO CODES CURRENTLY PENDING OR PRESENT!!! Engine is smooth & easy starting. Undermaintained & abused by hi mileage owner. "Tune" 6 components consisted of spark plugs / filters(not fuel filter however)& ignition coil ass'y being a 1 piece co...
March 07, 2007
2001 Lincoln LS 3.9L Poor Idle Quality, Misfire, MIL Lamp on VIN: 1LNHM87A21
P0304: Missfire on cylinder 4. This car came in for rough idle and check engine light on. The service codes are PO172, PO174, PO304 and PO1000. The customer has tried to cleared the codes before bringing the vehicle to shop. The engine runs rough at idling and the misfire malfunction monito...
March 07, 2007
1999 Mercedes-Benz C230 Kompressor 2.3L Misfire VIN: WDBHA24G6X
P0304: misfire 4cyl. ... check engine light was on code p0302 stored. during road test noticed fuel trim was up to 21%. checked state of tune ok . replaced m/f sensor and re-tested fuel trim now at -3%. returned vehicle to customer. about a week l...
March 08, 2007
2004 Honda S2000 2.2L MIL Lamp on VIN: JHMAP21464
P0304: Cylinder 4 Misfire Detected. ... missfire 1 and 4, and also random missfire, clear code. second time check engine light on with missfire #4 and factory code p1399 for igntion missfire. I usually run in to acura and honda with valve adjustment that is off and cause this, but at this time i...
March 09, 2007
1999 Mercedes-Benz ML320 3.2L Hesitation, Cuts out, Misfire, MIL Lamp on VIN: 4JGAB54E4X
P0304: cyl 4 misfire. Vehicle stalls out at above 1/2 throttle with excessive missfires. Fuel pressure is good. Spark plugs are new. All coils operational. Vehicle idles good. Tested new maf sensor, no change. Checked voltage out puts from throttle actuator to ecm. Found from pin 7...
March 12, 2007
1997 Dodge Ram 1500 Truck 5.2L Poor Idle Quality, Misfire, MIL Lamp on, LOW POWER VIN: 3B7HF13Y9V
P0304: Cylinder 4 Misfire Detected. thank's for your time people!i think codes were tripped by customer pulling off spark plug wires trying to pick out rough idle. after coil was replaced customer noticed lack of power compared to before.if you get rpm's over 3000 seems to come alive.also notice...
March 14, 2007
1999 Mercury Cougar 2.5L Misfire, MIL Lamp on VIN: 1ZYFT61L2X
missfire codes returning can not get monitors to run
March 14, 2007
2001 Toyota Avalon XL 3.0L Misfire, MIL Lamp on VIN: 4T1BF28B01
P0304: Cylinder 4 Misfire Detected. Dear fellow techs this should have been easy.This toyota came in for miss fire and flashing cel. Car never had spark plugs. removed manifold replaced spark plugs inspect coil and ohm check injectors reassembled all. No change in problem.swapped coil from good ...
March 14, 2007
1999 Mercury Cougar 2.5L Misfire, MIL Lamp on VIN: 1ZYFT61L2X
missfire codes returning can not get monitors to run
March 16, 2007
2005 Chevrolet Impala 3.4L Misfire VIN: 2G1WF52E95
P0304: miss fire. breaks down under heavy accel, over 3000 rpm. has new coil , injector, wire, plug and new valve springs on no. 4 cyl. new computer, new cat. convertor. also removed exaust pipe from muffler back
March 21, 2007
2003 Acura CL Type-S 3.2L Poor Idle Quality, Misfire, MIL Lamp on VIN: 19UYA41603
P0304: Cylinder 4 Misfire Detected. vehicle has misfire at idle only varies slight to signifigant. fuel trim adjusting for rich condition short and long term.misfire codes come and go fuel trim adjust constant.
March 26, 2007
2001 Lincoln LS 3.9L intermittant misfire VIN: 1LNHM87A21
P0304: cylinder 4 misfire. ... (p0300/p0304). cant feel a misfire, on scan data ltft -10 to -25. on o2, the front ones have good crosscounts in a normal range, the rear o2's, bank one around 60, bank 2 around 800. anyone seen this before? thank in adva...
March 29, 2007
2000 Honda CR-V LX 2.0L Poor Idle Quality, Cuts out, Misfire VIN: JHLRD28461
P0304: Cylinder 4 Misfire Detected. vehicle presents when cold runs extremly rough at idle/ lean once starts to warm will idle but poorly and is drivable.map sensor at idle reads approx 1.4-1.5 volts with a vac reading of approx 14 inches... If it had one i would say EGR is stuck open only codes...
March 02, 2007
1996 Ford Explorer Eddie Bauer 4.0L Poor Idle Quality, Misfire VIN: 1FMDU34X9T
P0304: 4 misfire. Hi all Got this explorer yesterday customer replaced plugs-wires-coil-fuel filter for this miss, still there. dead miss #4 I check codes, po304 active but #2 failed also in mode6, check vac leaks,firing order,compression, fuel pressure,spark all ok, slight int...
March 03, 2007
2002 Jaguar Vanden Plas 4.0L Poor Idle Quality, Misfire VIN: SAJDA24C82
P0304: miss fire cyl 4. HELLO GROUP: I need some help on this car, no matter what i do, it keeps on miss firing. Before injector flush it was showing miss fire cyl 1 2 and 4, now cyl 7 and 8. I've checked crank angle sensor wave form , it looked good. Inspected flywheel for warpage a...
March 05, 2007
2000 Jeep Cherokee Sport 4.0L Poor Idle Quality, f trim / O2 heater VIN: 1J4FF48S4Y
P0304: Cylinder 4 Misfire Detected. NO CODES CURRENTLY PENDING OR PRESENT!!! Engine is smooth & easy starting. Undermaintained & abused by hi mileage owner. "Tune" 6 components consisted of spark plugs / filters(not fuel filter however)& ignition coil ass'y being a 1 piece co...
March 07, 2007
2001 Lincoln LS 3.9L Poor Idle Quality, Misfire, MIL Lamp on VIN: 1LNHM87A21
P0304: Missfire on cylinder 4. This car came in for rough idle and check engine light on. The service codes are PO172, PO174, PO304 and PO1000. The customer has tried to cleared the codes before bringing the vehicle to shop. The engine runs rough at idling and the misfire malfunction monito...
March 07, 2007
1999 Mercedes-Benz C230 Kompressor 2.3L Misfire VIN: WDBHA24G6X
P0304: misfire 4cyl. ... check engine light was on code p0302 stored. during road test noticed fuel trim was up to 21%. checked state of tune ok . replaced m/f sensor and re-tested fuel trim now at -3%. returned vehicle to customer. about a week l...
March 08, 2007
2004 Honda S2000 2.2L MIL Lamp on VIN: JHMAP21464
P0304: Cylinder 4 Misfire Detected. ... missfire 1 and 4, and also random missfire, clear code. second time check engine light on with missfire #4 and factory code p1399 for igntion missfire. I usually run in to acura and honda with valve adjustment that is off and cause this, but at this time i...
March 09, 2007
1999 Mercedes-Benz ML320 3.2L Hesitation, Cuts out, Misfire, MIL Lamp on VIN: 4JGAB54E4X
P0304: cyl 4 misfire. Vehicle stalls out at above 1/2 throttle with excessive missfires. Fuel pressure is good. Spark plugs are new. All coils operational. Vehicle idles good. Tested new maf sensor, no change. Checked voltage out puts from throttle actuator to ecm. Found from pin 7...
March 12, 2007
1997 Dodge Ram 1500 Truck 5.2L Poor Idle Quality, Misfire, MIL Lamp on, LOW POWER VIN: 3B7HF13Y9V
P0304: Cylinder 4 Misfire Detected. thank's for your time people!i think codes were tripped by customer pulling off spark plug wires trying to pick out rough idle. after coil was replaced customer noticed lack of power compared to before.if you get rpm's over 3000 seems to come alive.also notice...
March 14, 2007
1999 Mercury Cougar 2.5L Misfire, MIL Lamp on VIN: 1ZYFT61L2X
missfire codes returning can not get monitors to run
March 14, 2007
2001 Toyota Avalon XL 3.0L Misfire, MIL Lamp on VIN: 4T1BF28B01
P0304: Cylinder 4 Misfire Detected. Dear fellow techs this should have been easy.This toyota came in for miss fire and flashing cel. Car never had spark plugs. removed manifold replaced spark plugs inspect coil and ohm check injectors reassembled all. No change in problem.swapped coil from good ...
March 14, 2007
1999 Mercury Cougar 2.5L Misfire, MIL Lamp on VIN: 1ZYFT61L2X
missfire codes returning can not get monitors to run
March 16, 2007
2005 Chevrolet Impala 3.4L Misfire VIN: 2G1WF52E95
P0304: miss fire. breaks down under heavy accel, over 3000 rpm. has new coil , injector, wire, plug and new valve springs on no. 4 cyl. new computer, new cat. convertor. also removed exaust pipe from muffler back
March 21, 2007
2003 Acura CL Type-S 3.2L Poor Idle Quality, Misfire, MIL Lamp on VIN: 19UYA41603
P0304: Cylinder 4 Misfire Detected. vehicle has misfire at idle only varies slight to signifigant. fuel trim adjusting for rich condition short and long term.misfire codes come and go fuel trim adjust constant.
March 26, 2007
2001 Lincoln LS 3.9L intermittant misfire VIN: 1LNHM87A21
P0304: cylinder 4 misfire. ... (p0300/p0304). cant feel a misfire, on scan data ltft -10 to -25. on o2, the front ones have good crosscounts in a normal range, the rear o2's, bank one around 60, bank 2 around 800. anyone seen this before? thank in adva...
March 29, 2007