fuel pump relay expert needed for 87 420
What makes the fuel pump stop after about one second if the car key is placed in position II, but not started? Is it part of the relay, is it part of the "fuel injection computer" or is there a sensor that tells the relay that the engine is not running?
My car ('87 420 SEL, W126) has this problem since the transmission front pump seal was replaced (or since I replaced the fuel pumps, filter etc., which was basically finished the day before I brought the car to the dealer for the transmission).
I am about to buy a new relay but would just be sure that it is really the relay and not some sensor or a loose connection to a sensor. The dealer told me his transmission work is fine and has nothing to do with the fuel pump relay.
Thanks for your help, it is appreciated.