Fuel Pump running with key off?
 

I was tinkering in the garage the other night when I heard a sound begin at the rear of my xD. It sounded like the fuel pump. It went on for a minute or so until I unscrewed/screwed the gas cap. Why would the fuel pump charge if the key is off? Was it something else?

There is an electric vacuum pump under the rear floor of the car, inside a black plastic box, near the fuel tank. It is there for emissions purposes to pull a vacuum on the tank to check for possible vapor leaks. It will run occaisionally for several seconds after you shut the car off to test the evaporative emissions system for the OBDII system and determine if it is functioning correctly or if it needs to turn on the check engine light becuase there is a problem.

If memory serves me correctly there is a reference to it in the owners manual and to not be alarmed should you hear it working.

What this guy said. It should only run for a short amount of time and then shut off. A friend of mine had the pump on his 2002 SS stick and it would run constantly until you pulled the terminals off the battery. :boxed:

Cool. Thanks guys.