2002 jimmy misfires at high rpms

[shandragon]

I have a 2002 jimmy with a 4.3 vortex engine that misfires at around 4000 plus RPM. I have changed MAF, distributor, crank sensor, fuel filter and no codes come up when scanned.

 

[Molson02536]

I have a 2002 jimmy with a 4.3 vortex engine that misfires at around 4000 plus RPM. I have changed MAF, distributor, crank sensor, fuel filter and no codes come up when scanned.

Check your distributor shaft for play. Take the cap and rotor off, and wiggle it side to side and up and down, if its got some play, its on the way out. Random misfire is mostly cause by a wobbly distributor shaft, its really the only part that can make a random misfire.

The other issues also could be the rotor and cap your using, after market rotor and cap's seem to have more issues then OEM's. If you do get after market one's make sure you but the cap with brass sleeve to eliminate miss fire issues.

http://www.accel-ignition.com/Produ...onName=Select+Aspiration&brandName=All+Brands

http://www.accel-ignition.com/Produ...onName=Select+Aspiration&brandName=All+Brands