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Q: Misfire in Cylinder #3 (P0303) / Random Misfire (P0300) on 1997 Chevrolet Lumina

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Car started running rough and sound terrible. Check engine light came on and started blinking. Got it home put a code reader to it and got P0303 and P0300. I have changed the spark plug and wires, replaced the fuel injector, and replaced the fuel filter; still having issues. I cleared the codes with the code reader after making all the above repairs....turned on the car and the check engine light began blinking again after a few moments. Engine sounds better but the P0303 and P0300codes came back. What could the problem be now? Ignition Coils?
No car image 94a1663db56199c5353592009e34aaa51078a2469bed068bb8d6f0ba43accf97
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Replace all 3 the coil packs. You could have a compression problem. Not enough info provided.
I have now replaced the #3 coil and the MAF sensor. Codes cleared for a moment longer this time, but came back...P0303 misfire detected in cyl #3, however, the detailed code P0300 seems to be the underlining problem.

More details:

Checked fuel pressure...good reading there.
Checked all wires and plugs...only #3 plug was a bit dirty...changed that and all the wires.
Checked the injectors and replaced the #3 injector...after this repair the car ran better.
Replaced the #3 and #6 coil pack.
Replaced the MAF sensor...after which the car ran a bit better but still a bit rough.

Next I am going to do a compression test.

What other details could I give to get a little more help with this problem??
Please help?!?
Thanks from the Greasymess.
If you haven't fixed this yet... Check for fuel pressure. I am having the same problem.
I was having the same problem replaced all of the things you did turned out to be the fuel pump which by the way is 300.00 but car is running fine now.
I was having the same problem replaced everything you did turned out to be the fuel pump which by the way is 300.00 but car is running fine now. Good luck.
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