Troubleshooting the fuel pump

The voltage to the electric fuel pump is supplied by the relay. Starting from the engine start phase, the pump delivers fresh fuel to the injectors. The second relay starts working when the engine is not running with the ignition on (the control unit no longer receives speed pulses). The relay then interrupts the current supply by means of a safety switch in the engine control unit. Thanks to this, for example, after an accident, gasoline cannot leak out. Checking the fuel pump is a workshop job. When troubleshooting, limit yourself to the following items.

Switch off the ignition.

Loosen the fuel injection line on the distributor - keep a rag ready to catch the splashing gasoline.

Even with the engine off, some gasoline should come out because the fuel system is under pressure.

If the connector remains dry, switch on the ignition for a short time (do not operate the starter).

If the pump does not start, check the fuse or safety relay.

If gasoline still does not flow, check the pump relay.

Now the fuel pump should work.

Otherwise, remove the cover under the rear seat and gently tap the pump housing with a small hammer - this sometimes helps.




If possible, also check that the electrical connections of the pump are properly fastened.

If the pump still does not work, check the voltage with a diode voltage indicator (a normal warning light would damage the control box). Don't forget to turn on the ignition first.

If voltage is present, the pump is faulty, or there is no continuity in the connected wire, your own chances of repairing faulty pumps are slim, so it's best to install a new pump.

If the pump is running, but there is no fuel in the discharge line, then the fuel filter or fuel line is clogged, or maybe just kinked.