Mechanics

CHEVY MISFIRE P0300

1997 Chevrolet Truck

Engine Performance problem
1997 Chevy Truck V8 Four Wheel Drive Automatic 244000 miles

Ok I started with the basics, fuel is a solid 55-60 even under load driving. I diagnosed the Ignition module as bad (had it tested) failed low and high rpm. I then replaced the wires, cap, rotor and coil. Before and after I replaced all of those I have an intermittent spark issue. I am using and adjustable spark tester and its set at approx 35k. Its a clean blue spark but it misses every few sparks. The truck has been around a lot so am I looking at cam and crank sensors? The gap in spark gets worse as rpms go up. Also it runs just fine when its cold up to about 1/2 mile, then it chugs and doesn't wanna move.
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Mole1333
November 8, 2010.




Misfire P0300 is usually caused by vacuum leaks and bad fuel.

Tiny
Rasmataz
Nov 8, 2010.
I am getting no fire on my 1997 chevy truck I have replaced sensors, coils etc. I am not getting any codes out of my computer can anyone help.
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Tiny
Jasonj343
Nov 12, 2010.

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