4.3 Vortec, 60,000 on engine, just changed spider injection and nut kit, spark plugs, scanned it and shows no codes, starts fine, runs good until its warmed up, runs rough at idle after warmed up, acceleratess fine, doesn't miss when rpms increased, runs fine when driving down the road, new fuel pump and fuel filter about 7,000 miles ago, have not checked egr valve, but did install a egr gasket with the screen awhile back, (maybe plugged?)Right after changing the spider injection and first starting the engine, it ran terrible, but after revving it up a fews times it ran smooth, I let it set and run for 20 minutes and revved it put in gear while sitting there and ran great fully warmed up, then drove it around the block, pulled into driveway and when I stopped, it was running rough again at idle. Couldn't find vacuum leaks, cat has never been replaced.I cleaned the idle air valve, and nothing
have the same problem?
Monday, September 17th, 2012 AT 3:42 PM