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1979 fuel pump prob/question

Hello,

A buddythat has a local vw shop had me come by to trouble shoot the FI on a customer's car (he is old school and does not care to lear FI) , Well, I found a vacuum leak that was causing most of the problems., but then i noticed that when the key was turned on, the fuel pump came on AND STAYED ON. It dit not go off after a few seconds. So, I traced the wires all the way to the relay, and they were not changed....they were stock. Then i tested double relay per Bentley, and it was fine. I cannot figure what is making the pump stay on all the time.

Any ideas?

Reply to
vgonman
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Pump is not supposed to come on for a few seconds and then turn off (on a Type 1 or 2). You may be thinking of Type 3.

On a Type 1, the pump only begins to run when the starter is running. Then the Dbl Relay keeps the pump running when the AFM senses that the engine has started.

This page of my web site:

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for the FI section. There is a simplifieddiagram of the FI controls. Unplug the AFM and see if the pump still runs with key On. If that kills it, the internal vane switch may be stuck.

There is a wire from 86a on the Dbl Relay to the Starter solenoid. Check underneath if that's in the correct place.

Speedy Jim

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Reply to
Speedy Jim

Thank you for refreshing my memory! I had forgotten about those contact points in the AFM. Someone must have been tinkering in there on this car.

You are right, the fuel pump comes > vg>

Reply to
vgonman

Reply to
vgonman

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