Engine revs when vehicle stopped

chevrolet
suburban

#1

My engine revs up no matter if the thing is hot or cold when I come to a stop at a red light, SOMETIMES. Other times it will idle at 100 and then wants to idle around 1000 and has idled as high as 1200. I’ve been told EGR, TPS, Idle Control Motor, or Intake gaskets. I did have a code 22 which occurred after a friend unplugged the TPS and reconnected it, but no other codes or check engine lights. Tuned engine 2 weeks ago, but problem still persists. Where do I start and what equipment do I need. I am a professional diesel tech, but not so much with gas.


#2

Code P022 is for a problem with the variable cam timing, which can cause idle problems:

http://www.obd-codes.com/p0022

I’d start by checking the VCT solenoid as described above. Then check idle air control valve (it can be cleaned if necessary). Also check for vacuum leaks.


#3

You need to tell us what year it is and what engine is in it. I’m assuming it is pre-1996 and the 22 code is OBDI rather than OBDII. But knowing which engine might also be helpful.

I would clean the idle air control valve and the throttle body for starters. And check for vacuum leaks.


#4

What’s the year and engine of your Suburban?