Fuel pump not working properly?

1978 VOLKSWAGEN BEETLE
82,000 MILES • 1.6L • 4 CYL • 2WD • MANUAL
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JKBROWN2
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The fuel pump is not engaging when the ignition switch in turn to the start position.
Feb 24, 2023 at 7:38 AM
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JACOBANDNICKOLAS
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Hi,

The fuel pump is mechanical and not electric (unless someone changed it). It won't pump fuel until the engine is turning.

Let me know.

Joe
Feb 24, 2023 at 9:38 PM
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JKBROWN2
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It's factory fuel injected, it has to be electric.
Feb 27, 2023 at 7:32 AM
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JACOBANDNICKOLAS
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Hi,

You are correct. Sorry about that. They did have ones with mechanical pumps as well. It seems so odd to think of a 1978 that was fuel injected. It was very cutting-edge for the times.

Okay, when the key is first turned on, the pump should run for a couple of seconds. I believe that is where you are having the issue. Power is provided by a timed relay that energizes the pump for a short time. Once the vehicle is running, power is supplied via the starter solenoid.

Now here is my problem. Because of the model year, I have no wiring schematics to tell you where to look for the relay. It should be close to the fuse box. That is where I would start checking. Locate the relay and remove and inspect its connectors. Also, here is a link that explains how to test a relay:

https://www.2carpros.com/articles/how-to-check-an-electrical-relay-and-wiring-control-circuit

See if you are able to locate the relays. Again, sorry I don't have the schematics or fuse panel legend.

Let me know.

Joe
Feb 28, 2023 at 6:18 PM
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JKBROWN2
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Follow this link for schematics:

www.speedyjim.net/schem/fi.htm


Thanks
Mar 3, 2023 at 6:09 AM
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JACOBANDNICKOLAS
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Hi,

Thanks for the schematic. That is extremely helpful, and I know for sure it will help others in the future.

Take care and thanks again,

Joe
Mar 3, 2023 at 7:38 PM