Mechanics

ENGINE RUNNING TOO FAST

Chevrolet Other

I have a 2001 Chevy 2500HD with a 6.0L engine. 5 spd manual trans. 120,000 miles. After cruising at 60-65mph for about 30 minutes or more. The engine wants to run at 3,000 RPM and doesn't slow doown til you shut it off. The EGR valve was bad and I replaced it, but it still wants to run away with me. What is the problem? No other trouble codes exist except for the fuel guage problem common on most of these trucks. Can anyone help me?
Delmar cowboy492000@yahoo. Com
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DelmarH51
June 7, 2006.



I have the same problem in my 2001 blazer 2wd 5 speed manual (83,000 mi). After cruise of about 20 minutes or more, the engine revs to around 3000 rpm in neutral for a few seconds, then returns to normal idle. When still on the highway, it will actually accelerate the car if in a low enough gear. Worked the throttle cable and didnt find any sticking.

Tiny
Jgslick
Jun 8, 2006.
Not sure if you're still looking for an answer to your problem, but I removed and cleaned the mass airflow sensor (between the air filter box and intake), disassembled it and cleaned the sensors with quick drying electronic contact cleaner. Fixed the problem. Most places say that you need to replace this part if it is dirty because the autoclean cycle isnt working properly, and eventually im sure it would need to get replaced, but a five dollar can of cleaner is better than a hundred dollar sensor that isnt totally necessary.

Tiny
Jgslick
Aug 27, 2006.
I've also been told to check the idle air control valve for deposits. And that it can be fixed by running an injection system cleaning machine on it. It costs $ 140.00 so I haven't done that yet. I'll try the mass air flow sensor first, thanks.

Tiny
DelmarH51
Aug 27, 2006.