the fuel pump relay. Worth checking if you don't know how long it's been in the car. To get at it, you will need to remove the ashtray and cover behind it, prise off the cigar lighter surround, remove the two screws holding it, then remove the cigar lighter and the shelf below it to reveal the relay panel. The fuel pump relay is the green one on the left at the back. Then if you want to check it read this thread, and if need be make a temporary repair.