1993 Chevy Truck rpm varies

1993 CHEVROLET TRUCK
136,000 MILES • V8 • 4WD • AUTOMATIC
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BOXER55
  • MEMBER
  • 2 POSTS
1993 chevy 1/2 ton with 350. when the engine warms up the engine rpm varies around 50 to 75 rpm's when driving between 25 and 40 mph. it idles ok and runs good at higher speeds.
Mar 14, 2009 at 1:36 PM
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JDL
  • CAR REPAIR CONTRIBUTOR
  • 16,098 POSTS
Hello, how long since a tune-up? Are there any codes? How is the fuel pressure? If you have a dmm, you can look at sensor signals, see if their acting like they should. A scanner that will show live engine data is quicker. Sometimes the live engine data looks ok and you still have the problem. You have to start somewhere.
Mar 14, 2009 at 2:12 PM
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