Sounds like the Gas Cap Lock as others have mentioned. It's a solenoid, and these have been known to fail.
Try pulling the manual release inside the passenger side door jamb and see if it duplicates the noise, or if it fixes the issue.
It's not in the door, but just forward of the passenger door behand the door pillar.
If not, you're probably looking at replacement. The part is called actuator and the PN# is 996.624.113.00 .
|