95 tahoe idle up and down
 

hi. I have a 1995 tahoe 106,000 miles on it. it recently started acting up i. It runs fine when its cold outside, but when it warms up it runs rough stalls and idles up and down about 800 rpms. almost to stall and then back up to normal. I replaced the throttle control sensor, but the problem has persisted any help would be greatly appreciated. thanks, chuck

is it only at idle? could be that the idle air control valve and maybe the egr need cleaning.

oh yeah, welcome to our forums!!

it does it while at idle, but also on highway when you let off the gas. thanks, chuck

Yep, sounds like the IAC is acting up.

changed out the iac, and map sensor. still no luck. go out in the morning when its cool out runs good. after work 55 degrees out starts the up and down idle. any ideas? thanks chuck

possibly egr. maybe timing. maybe

thanks maxxman. I am going to check the egr tomorrow. just not sure where it is located. thanks for all your help. chuck

is it throttle body injected, or a vortec?

it is throttle body