1992 GMC C1500 Very Poor Acceleration

1992 GMC C1500
150,000 MILES • V8 • 2WD • AUTOMATIC
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JOHNKLASER
  • MEMBER
  • 1 POST
Truck will idle although with some stumble. Accelerating normally is near impossible as the engine will stall. If you can get the truck up to speed (maybe 20mph) and then mash the accelerator there is great acceleration and no problem with power. Have already replaced the plugs, cap, rotor, spark plug wires, injectors (TBI), TPS (throttle position sensor), and the fuel filter
Oct 16, 2008 at 1:32 PM
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MERLIN2021
  • CAR REPAIR CONTRIBUTOR
  • 17,250 POSTS
Clean the MAF and . You may have a vacuum leak, get a can of spray gumout, spray the vac lines and maniflod area, when the idle changes, youve found the leak! You want the engine running and spray on the outside but do direct the stream onto the hoses, if it is a vacuum leak, the engine idle will change speed, then you have detected a leak, repair the vacuum leak and see how it runs! If no leaks found check the fuel pressure, and is your Service engine soon light on?
Oct 16, 2008 at 5:14 PM
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