Truck spark knocks a lot under moderate loads. Premium fuel helps a little but not much. Put a code reader on it but it doesn't throw any codes. Truck has done this for many miles. I believe the spark knock is worse in the spring and summer when temperatures warm up. I've also tried several bottles of the more expensive fuel injector cleaner, no help. Truck is stock including new Motorcraft plugs. It does have a K&N air cleaner which I service every 20,000 miles.
Oil pressure needle also fluctuates at idle when the engine is warm. It has done this for many 60,000miles or so. I use 30 W in the summer and that helps.
Oil pressure needle also fluctuates at idle when the engine is warm. It has done this for many 60,000miles or so. I use 30 W in the summer and that helps.
Apr 1, 2010 at 2:16 PM
