BMW said I don't have one on my model. It's a 2004 x5 4.4 with 86 k miles. Love it but they also said I have low compression in one cylinder only putting out 80 instead of 110 which BMW says is acceptable. I find this hard to believe. They want to change my head gasket and new rings at 6,000.00. It has not started once a week and if it sits it will start. I have a brand new battery and 2 places says my charging system is good. Can it be the fuel pump? It cranks over and clicks but not enough to turn the engine over