Truck rough idling problems

1993 GMC C1500
210,000 MILES • V8 • 2WD • AUTOMATIC
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GMCSIERRA
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  • 1 POST
I have a 1993 GMC Sierra with 210,000 miles. 5.7 V8. When I start the truck and place my foot on the gas to take off between 0-2000rpm it sputters and spits. I also notice a hint of fuel smell. After it gets up pass 2000rpms it seems to accelerate fine, normally. But when I take my foot off the pedal it loses the rpms and it dies out. What is the problem?!?
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Mar 17, 2011 at 2:07 PM
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JDL
  • ✓ASE Certified Mechanic
  • 16,098 POSTS
  • ASE Certified Mechanic
How long since a tune-up? Any applicable mil codes? You can check those codes yourself. Use a gage and check fuel pressure. If you can do it without hurting anything, block/clamp the fuel return line. See if pressure holds? Unless your trying to test pump, don't block return line until pump stops.

Check and clean the idle air system.
Mar 18, 2011 at 6:03 PM
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