This fuel pump was taken off my mercedes 1989 300 SL and is fully working as has been tested. It is for petrol engines. We replaced it with a brand new one ( the box shown and spare bits are from the new box). It turned out that it was not the fuel pump that was the problem but something else electrical with the car. It now makes little sense to replace the new fuel pump installed again, as it would cost too much to do. So the result is a spare fuel pump that has nothing wrong with it. A good replacement if your fuel pump has gone wrong or you need one. If there are any issues you can return it to me for a refund on the purchase price. Please just check it fits your model first before you buy it !