99 Jimmy, 4.3L engine, 4x4.

Have had this issue for awhile, and the tune up I did didn't seem to take care of the problem.

For reference, I changed:

Cap
Rotor
Spark Plugs
Spark Plug Wires
Air Filter
Cleaned the MAF
Cleaned the Throttle Body

Made a big difference, but didn't clear up my issue.

Normally, I see 625-675 RPM when warm, according to my handheld scanner. However, lately I have been sitting in around 950-1000RPM after a 15 minute drive home from work.

Anyone know why this is? Any tips would be appreciated, can't seem to nail this one down. Not a major issue, but that tach sitting in the wrong spot just seems to grate on my nerves a little.

 

Air/idle sensor on side of Throttle body. Its a round sleeve that 2 types I believe. 1 unbolts on the side and the other has a bolt that holds it in. Be careful when removing wiggle it out. It has a rubber gasket that you'll reuse and have to grease it. Its just a plunger that gets carbon built up on it and can't be cleaned from the T/B. Hope this helps!

 

OK, I'll have to give that a look. My throttle body was gummed up pretty bad, so this could easily be it. Thanks for the help, I'll update after I fix it, assuming I can get to it this weekend.

 

MIne purrrrs like a kitten now. Take the whole throttle body off. Its a lot easier to clean out with break clean and wipe out all the carbon build up. .02