Quote:
Originally posted by jjcollier
Dumb question: So it is definitely odd/wrong that my fuel pump is NOT buzzing at start up?
Thanks too for the above.
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The fuel pump should not buzz when the key is switched on. The erroneously called fuel pump relay is actually a safety relay that allows energizing the fuel pump only when the engine is CRANKING. Once the flapper switch opens (indicating airflow to the engine) the fuel pump relay is de-energized and the fuel pump continues to run on the ignition switched system. If the flapper valve closes (no airflow in say a crash) the relay is energized and the fuel pump stops. The fuel pump can be made to run all the time the ignition switch is turned on by removing the fuel relay and jumpering contacts 87a and 30.