Check your oil at the dipstick to see if you are burning any. Open the oil cap see if there is any sign of a white/tan mussy substance. This is a sign of water getting into your oil. Then check the coolent tank to see if there are any traces of oil in your water. The oil will be floating on top of the water. Either one of these means its a head gasket. During a head gasket change you will need to replace that wiring harness because as soon as you move it you'll get electrical problems after you put it back together if not replaced. This engine has pretty good oil seals in the head not like the M103 engine and has a very stout bottom end so, for now I count seals and rings out.