There is an important part in the fuel system named fuel rail, and you can find it on diesel and some gasoline injected vehicles. The function of the fuel rail is to monitor the fuel pressure that is present. Here are some symptoms showing that the fuel rail in your car is failing: if you are experiencing a hard starting; if there are some engine performance issues, like decrease in power, acceleration and fuel efficiency; if the Check Engine Light in your panel is on, you should stop driving immediately and check it to see if the replacement is necessary. Some of parts are checked during the routine service and regular maintenance, but except this, you are supposed to know the symptoms of a failing parts and check it in time. Once you decide to change, you are glad to offer you BMW genuine OEM fuel rail with a discounted price.