Just purchased a 1996 Mercedes C220 and am really happy with it. Just have one minor problem that I'm hoping I can solve without having to take the vehicle to the dealership service department.

I've recently noticed that my trunk mounted vacuum pump stays on for about 10 minutes after I start the vehicle. I find this strange because I have had no problem with the remote locks. The noise can be heard when the car is idling low. The pump will run for short intervals--4 seconds on, then 4 seconds off. After about 10 minutes of driving, it goes away. Today, I disconnected the pump in fear that I will burn it out. Are there any electrical relays or components that could cause this to stick? I know the problem is not the pump. Today I tested a used pump in the vehicle and got the same result.

This website rules! Thanks in advance!