1997 Chevy Truck Misfire P0300

1997 CHEVROLET TRUCK
244,000 MILES • V8 • 4WD • AUTOMATIC
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MOLE1333
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  • 1 POST
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.
Nov 8, 2010 at 9:16 PM
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RASMATAZ
  • ASE Certified Mechanic
  • 75,992 POSTS
  • ASE Certified Mechanic
Misfire P0300 is usually caused by vacuum leaks and bad fuel.
Nov 8, 2010 at 9:34 PM
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JASONJ343
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  • 2 POSTS
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.
Nov 12, 2010 at 8:23 PM
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