2 misfires HELP?

[Maxx726]

Got a problem, car has CEL flashes when I start car and sounds like the car is choking, after 10 seconds cel stops flashes but is still on and car sounds normal, fuel injectors? I replaced my old ones with used ones worked fine for a day and started doing this again after. Any suggestions? (coil packs have been replaced under recall, and changed spark plugs a month ago) I scanned and have the codes P0300 P0301 P0303 for misfires.

[STOICH]

Swap ign coils around and see if the misfire follows. Then do the same with the injectors. If the misfire doesn't follow either, check your ign coil harness for cracks. It may need to be replaced.

Also make sure the valve cover isn't leaking oil into the plug ports.

[Maxx726]

Swap ign coils around and see if the misfire follows. Then do the same with the injectors. If the misfire doesn't follow either, check your ign coil harness for cracks. It may need to be replaced.

Also make sure the valve cover isn't leaking oil into the plug ports.

if the ign coil harness is cracked wouldnt the CEL stay on always? because sometimes it comes off n drives normally and then lights up again and starts bad

[STOICH]

Not really. I would never relate the behavior of a CEL to eliminate possible issues. They can be very sporadic.

[Maxx726]

Not really. I would never relate the behavior of a CEL to eliminate possible issues. They can be very sporadic.

where could they crack? i checked the harnness on top looks to be in good shape, maybe its bad where i cant see it? also another important thing is I replaced my fuel injectors with used ones and after the car startedup perfectly no codes or anything but thenext day it started starting bad and CEL light on

[STOICH]

Clear your codes.
Move offending cylinder injector.
Check codes again and see if the misfire code jumps with the injector.

If not, do the same to your ign coils.

If the misfire doesn't follow the moved parts, you're most likely looking at a plug or harness issue.

[Maxx726]

Clear your codes.
Move offending cylinder injector.
Check codes again and see if the misfire code jumps with the injector.

If not, do the same to your ign coils.

If the misfire doesn't follow the moved parts, you're most likely looking at a plug or harness issue.

will go ahead and try that, thanks for the advice

[Maxx726]

Clear your codes.
Move offending cylinder injector.
Check codes again and see if the misfire code jumps with the injector.

If not, do the same to your ign coils.

If the misfire doesn't follow the moved parts, you're most likely looking at a plug or harness issue.

can oil 0w-40 cause this problem? my car has 97,000 miles

[Rockerchick]

No, your oil isn't going to cause this. Do as its been suggested already and swap your coils around for starters.

[Maxx726]

Replaced everything possible on this P.O.S. jetta and still misfiring, when i start the car in the morning it sounds like its choking.. and CEL flashes, after 5 seconds the idle smooths out and CEL stays lit. I replaced coil packs, spark plugs, coil pack harness, crankshaft position sensor. cleaned MAF. idk what else could be wrong. please help im supposed to get rid of this shty VW this weekend and i need to fix it by then.

[STOICH]

What happens when you run the car with the airflow sensor unplugged? Better?

[Maxx726]

What happens when you run the car with the airflow sensor unplugged? Better?

havent tried, sounds dangerous

[Rockerchick]

Its not. Unplug it and see what happens.

[Maxx726]

Its not. Unplug it and see what happens.

Idont think it can be a MAF causing my car to startup bad and misfiring..

[Rockerchick]

A bad MAF can cause a lot of problems. If you unplug the MAF and nothing changes or it gets better, then the MAF is bad. If it gets worse, MAF is fine. Its a quick, easy test. I'd go ahead and do it.

You also should try to keep all this stuff to one thread. It gets confusing when you have 2 going at once...

[Maxx726]

A bad MAF can cause a lot of problems. If you unplug the MAF and nothing changes or it gets better, then the MAF is bad. If it gets worse, MAF is fine. Its a quick, easy test. I'd go ahead and do it.

You also should try to keep all this stuff to one thread. It gets confusing when you have 2 going at once...

what do you mean by it gets better, and if it gets worse maf is fine??

Sorry its just hard to get people to reply and I really need help asap

[Rockerchick]

If you unplug the MAF and the car behaves worse than the MAF isn't your culprit. If nothing changes than your MAF is likely bad.

[Maxx726]

If you unplug the MAF and the car behaves worse than the MAF isn't your culprit. If nothing changes than your MAF is likely bad.

oh okay thanks, also should i unplug it while the car is running, or unplug it and start the car?

[redline1320]

Unplug while the car is running and let the car idle


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