Hey guys, recently purchased a 1996 GMC Jimmy. Runs great, good engine and recently rebuilt tranny. Only problems I had with it are at about 3k RPMs on the freeway it would sort of surge. Long story short I replaced air filter, fuel filter, MAF Sensor until I decided to try unplugging the EGR valve. It went away after I unplugged the EGR, and ran fine on the freeway. I read somewhere early GMCs had a problem with there EGRs where that surge was kinda normal. I tried cleaning my EGR valve but no luck. Before I go out and spend on another EGR valve, has anyone had this problem before? And is my diagnosis correct or could it possibly be a vacuum line perhaps? I appreciate any input. Thanks.
