P0304

[dantedawg]

go to the last thread for an updated one. problem not solved yet. need help.

so last week i scanned my car and this code came out. P0304, or cylinder 4 misfire. mechanic said it could be the ignition coil ( set of 2), could be the ignition wire set, spark plug connector. so we changed everything. cost me close to 500 dollars.

so no more problems. infact my car was running smoother as ever. but it came back. yesterday my car gave me the same problem, CEL came out, car was shaking. i stopped and scanned it. same shit! but this time i erased the code.

what could be the problem now? im going back to my mechanic monday and he said he'll check other stuff.

pls help. thanks

[xvvvz]

Year? Model? Engine series?

[dantedawg]

Originally posted by xvvvz
Year? Model? Engine series?

98 c230. i have 80xxx on the clock. got tuned p oil change at 78000

[First Benz]

Check and change your plugs. I'll bet money the #4 plug has carbon tracking on it.

Let me know what the plug looks like, they probably look like crap, and if they do, just throw some new ones in there, it'll probably fix the problem.

Eric

[dantedawg]

Originally posted by First Benz
Check and change your plugs. I'll bet money the #4 plug has carbon tracking on it.

Let me know what the plug looks like, they probably look like crap, and if they do, just throw some new ones in there, it'll probably fix the problem.

Eric

ill have the mechanic check the plugs. as far as i remember i had the plugs changed 2000 miles ago for tune up. thanks for the help though..ill update when i see my mechanic..

[dantedawg]

P0304 ( cylinder 4 misfire ) on 1998 c230


ok now..this week it happened 3x! i drive to work with no problem. after few hours when i start the engine, the car was shaking again as if its gonna die with the CEL on. i drove it for about 300 meters just to observe it. but i couldn't run it like that so i had to restart the car and went back to normal( not shaking).

again, the ignition coils are brandnew, the ignition wire set, and spark plug connector, all brand new. spark plugs are ok as well!
i saw the mechanic today and he couldn't figure out the problem. we looked at the fuel injector too but it doesnt make sense that after restarting the car, the car would run smooth even with the engine light is on. otherwise it would be choking the whole time.

i hope you guys can help me with this.

[JRE320]

Must be your fuel filter. You need to change the filter if you have not changed it.

[dantedawg]

Originally posted by JRE320
Must be your fuel filter. You need to change the filter if you have not changed it.


possibly. but then again...after restarting the engine, i can drive with no problem except for the CEL. its really strange..ill still check it...i believe the fuel filter is new too

[jnenad16]

could be the wiring harness.

nenad