Engine Performance problem
2002 GMC Yukon V8 All Wheel Drive Automatic 56,546 miles
took my truck to the gmc dealer for adiagnosis of a lack of power. The truck seemed to run good at an idle but lugged when I got on the throttle. I was told that it was missing on number six and it was either a broken valve spring or a fuel injector. At this point I took the truck home and did some looking.
-pulled off the valve cover, springs ok -changed fuel injector, no change -did a compression test, 150psi -did a compression test with both ajacent plugs removed, 150psi -moved plug, lead, and coil to different hole, no change -tested fuel pressure, ok -tested with noid lights, ok -sprayed intake while running with cleaner found no vacum leaks. Please help
Monday, January 12th, 2009 AT 3:05 PM