1999 GMC Yuckon Denali 145,000miles. It has a 5.7L vortec engine. I notice a rough vibration when idling. It isn't something big just something I notice a lot. I recently replaced The TP sensor, Spark Plugs, Spark Plug wires, Fuel Filter, Air Filter and serpentine belt. I just want it to idle nice and smooth. I am thinking it might be the Vehicles timing but don't want to waist all the money if it ain't the problem. I was wondering if there is anything else I can do to get rid of this rough/poor idle? When I replaced the spark plugs I noticed that one of my plugs had oil around the threads Is this something to worry about I checked my oil and noticed that it was low. What could this problem be?
Thursday, June 29th, 2006 AT 7:39 PM