Problem with my 01, need advice
Truck ran fine till this morning. Warmed her up for a few mins then hit the high idle for another few till the temp came up. Left work doing 15mph for a mile all good. Hit the highway and was good till 45-50mph then it started to run like ***, wouldn't rev to good, no power, just plain sluggish (oh yeah, engine light came on too). Pulled over and shut her down for a few seconds, fired her back up and the same thing. Switched tunes on my F5 and went back to stock to no avail. Was gonna have her towed but being 30+ miles up the mountain (expensive tow) I decided to limp her home. About 2 miles later the problem just went away and I was fine all the way home in any tune. Truck sat at home for 7 hours, I jumped in a few minutes ago and same problem, engine light on, idle kinda rough, sluggish. Left her sitting and used my lightning instead. Thinking it's the under valve cover harness (was suggested to me).
Anybody have any ideas whatz up? Truck has 125K miles. Thanks for any help guyz!!!