1998 GMC 1500 Idle RPM's

[MrBillPro]

Anyone know what the idle RPM should be on a 1998 GMC 1500 350 vortec 5.7.
Thanks Mr. Bill

[amac209]

usually it's around 800 if you install a scan tool it will tell you the desired idle and the actual idle. if the pcm is unable to adjust it where it wants it the check engine light will usually come on.

[J.T.COPE]

both chilton and haynes show 1000 rpm at idle.....mine of coarse doesnt it idles at 800....i pulled out the air idler valve and cleaned on the carbon of it and it idled at 1000 for about a week and went back to 800..if you ask me 1000 seems high.........hope that helps

[MrBillPro]

Originally Posted by J.T.COPE

pulled out the air idler valve and cleaned on the carbon of it

I have cleaned the throttle body itself with carb spray "it was pretty dirty" but I have no clue were the air idler valve is do they get pretty dirty? and if so could you direct me to were this might be on the throttle body.
Thanks Bill

[MrBillPro]

This has never happened in over 100,000 miles but i went to start my truck right after filling it up at the station the other day and it popped back thtough the throttle body, just one time and when i tried to start it it started ok just a few more turns than normal and it's running fine don't know maybe it was just a coincidence. I have new wires and rotor and cap was replaced about 6 months ago and new plugs probably one month ago they are the ACDelco's RAPIDFIRE High Performance Spark Plugs hope these are alright. Truck seems to run fine just seems to have to turn over a lot more than it did even at 93,000 miles to start
maybe no problems at all here but what else do you check I am 53 I grew up with the Points distributor and HEI so I am still trying to learn all this new stuff.