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spuggy spuggy is offline
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Join Date: Jul 2003
Location: Glorious Pac NW
Posts: 2,828
Far canal! I think the relays should be either on or off too. Sounds like they're being fed AC instead of DC!!

There's a safety feature on later cars whereby the pumps are disabled when the motor isn't actually running (air flapper moved off the stop). So you should be able to push the flapper down and see what it does (should start the pumps running). Don't do it too much, it'll squirt fuel into the motor too...

Ddn't you take this all apart for the fuel distributor? Sounds almost like the switch is right at the point that it can't make up it's mind whether to be open or closed, although it surely wouldn't do that fast enough to make the relays oscillate...

I think the switch breaks the ground return for the control circuit fuel pump relays when the flapper is at rest, but i'm not sure.

If the relays are flapping back and forth, think you need to trace the circuit back until you're getting sane control inputs for the relays and rectify the last link in the chain

You might be well advised to check any rewiring that was done, too... Good luck!
'77 S with '78 930 power and a few other things.
Old 11-26-2007, 08:12 PM
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