1988 GMC SIERRA wont start...tried everything

Asked by snowbirdsneedhelp Dec 17, 2013 at 10:03 PM about the 1988 GMC Sierra 1500 K1500 Standard Cab LB 4WD

Question type: Maintenance & Repair

1988 GMC Sierra 1500 5.7 L. Tranny went bad, had tranny rebuilt, had to pull motor to put tranny in. Put new tranny and motor back in. Started truck and it ran at idle perfectly for 1/2 hour. Got in truck to move it put foot on accelerator pedal truck died. Restarted idled fine, put foot on accelerator again and died. Each time I did this truck began to start rougher and rougher. Til it got to where it wouldnt start at all. Now truck wont start. checked fuel preesure at throttle body reads good within acceptable range, new distributor, new throttle body, traced all electrical lines for pinched wire all look good, put new fuel pump and tank in a year ago, new computer, new coil, throttle position sensor, ignition control module, temp sensor, plugs, and more. We have replaced everything there is to replace. Still won't start. Engine is turning over, have spark, fuel, and compression. Checked timing, checked compression on all cylinders. Took to 3 mechanics not one have any idea. Please help!

migration_judge_roy answered 10 years ago

The chassis ground is connected with a 1/0 battery cable...at the end of the black cable there is a lug that bolts there...use a wirebrush to make your main ground shiny and able to pull 300 amps comfortably here and the chassis where it bolts to...wirebrush make a SOLID ground connection to the chassis ground~...this was overlooked by three mechanics~

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migration_judge_roy answered 10 years ago

y'see the motor has it's own 1/0 connection to block near the base of the alternator...this one is fine because it kicks over....but the ignition system is working with "brown" power...do as I say and remove the corrosion from this main ground connection....okay?~

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