2001 Chevy Monte Carlo Acclearting / Tachometer Drops

2001 CHEVROLET MONTE CARLO
111,000 MILES • 6 CYL • 2WD • AUTOMATIC
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MONKEYBOY666
  • MEMBER
  • 2 POSTS
About 5-10 minutes after the car is started and is running normal city driving (35-45 MPH), when hitting teh gas to accelerate, the RPM's will go from 2000 RPM and decrease down to about 1100-1200 RPM. The car still runs fine, but just doesn't seem right. Taking foot off the gas and then accelaring again is OK. Sometimes the RPM will 'jump" from 1100-1200 to 1500 and then settle back down. CAR STILL FUNCTIONS FINE. The 'check engine' light came on once - flashing, but went right out and no longer has come back on. Already had computer replaced and fuel injectors cleaned when 'check engine' light came on and stayed on continuosly.
Jan 14, 2010 at 8:54 AM
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SCOTTY DEE
  • ASE Certified Mechanic
  • 592 POSTS
  • ASE Certified Mechanic
With a scan tool, start the engine and observe the engine speed parameter in the PCM data list. Question is does the engine speed parameter match the tachometer?

If yes it's an intermittent electrical problem on that circuit.

If no the cluster is bad.


When the SES light comes on and flashes, that means conditions are present that could damage the catalytic convertor.
Jan 26, 2010 at 8:35 PM
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