Engine Performance problem
1995 GMC Yukon V8 Four Wheel Drive Automatic 133000 miles
GMC Yukon 5.7L throttle body injection
My problem is above idle between 1000-2000 or so rpm or part throttle the engine misses and wants to stall but just recovers in time, idle and full throttle are not affected. My mechanic scanned the truck and the EGR is opening 100% with part throttle and causing the engine to run ruff, and after inspection the EGR soleniod was missing the little foam piece bellow the vacume line and thought debris might have got lodged inside and be the problem. So we replaced that and no luck, the EGR is opening fine, the TPS is working fine, plugs, cap, wires have been replaced BUT if the vacume line going to the solenoid is disconnected the problem goes away (although I didnt road test it just in neutral test anyway) the check engine light isnt on and there were no codes indicating any other problem.
I have searched everywhere online and all I have seen is the ilde bypass circut being clogged, o/2 sensors, vacume leaks, EGR and solenoid replacement. I really need this provlem fixed any help is much appreciated.
have the same problem?
Friday, April 18th, 2008 AT 1:00 AM