The V8 Owners Forum -

I have a 1988 Marcos Mantula fitted with a Rover 3.5 Vitesse EFI engine, when turning the ignition key to the 1st position the remote fitted fuel pump no longer kicks in for a few seconds to prime the fuel line to the fuel injection system, this use to work up until I drove the car into a large dip in the road cursing the sump guard to heavily hit the road and stopping the engine, I managed to restart the engine by disconnecting and then reconnecting the multiple electrical connection from the air flapper valve but not with the aid of the fuel priming, the fuel pump does run when the ignition is turned to the cranking position and allows the engine to run.

Check if the relays click when you power up…..chances are the relay has failed / not connecting in the socket.


Or one of the earths has come disconnected and once cranked being back fed through another system

Would be my guess

Ian

I've only worked with the ECU from the later system, 14CUX, if I've understood correctly the Vitesse uses the older 4CU system and it seems this controls the fuel pump differently.
It seems that during priming the fuel pump is controlled by a time delay circuit/relay, presumably a separate module to the ECU, while for continuous running the pump signal is provided by a switch in the Air Flow Meter, presumably this turns on when the flappy-flap is moved due to air flow.

Based on how you've explained the issue started it's likely that either the module which controls the prime has become dislodged/damaged or some of the wiring in this circuit has.