4.3L 93 c1500 Misfires and backfires
shotty1974
07-26-2009, 06:57 PM
4.3l chevy c1500 -- Replaced and or Tested ICM, TPS, EGR, EGR Selnoid, distributor cap, distributor rotor, Map Sensor, spark plugs and wires. Tested all vacuum line
At idol = 12inch
under load = around 19
My truck misfires and backfires at all speed and idol.
EXCEPT when I use the bypass for the timing. It forces the car into Base Timing mode. Then the car runs perfectly. The only thing left replace is knock sensor, IAC and PCM. At this point I feel almost certainly is a timing is since i can bypass and run smooth. Im at my wits end and sick of throwing money at the problem.
Please any suggestions or things I might of missed. Or any idea what could cause thanks..
At idol = 12inch
under load = around 19
My truck misfires and backfires at all speed and idol.
EXCEPT when I use the bypass for the timing. It forces the car into Base Timing mode. Then the car runs perfectly. The only thing left replace is knock sensor, IAC and PCM. At this point I feel almost certainly is a timing is since i can bypass and run smooth. Im at my wits end and sick of throwing money at the problem.
Please any suggestions or things I might of missed. Or any idea what could cause thanks..
troy1
08-06-2009, 08:31 PM
You need to pull the distributor and check the bushing and drive gear.
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