Thanks for the post Don. I'll follow up on it in more detail a bit later today. In the meantime, I've got a few questions:
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The Prime function (2-second run you hear before crank) bypasses the fuel pump relay.
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Is there a physically separate relay component for turning on the pump for the prime function? Or are there 2 relays in one package: one for prime and one for when the engine is running?
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The relay NO contact ("87") is actuated by the PCM (powertrain control module) during start and run
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Is this specifically for the 2001 Crown Vic 4.6L V8 -W? May I ask where you got this info from and if it's available somewhere online?
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verify pump gets power while cranking.
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Will do!
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You can also jumper across relay - Terminals "30" (+12V in) and "87" (not "87A"). Temporarily, of course, but OK for many minutes.
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If the previous test indicates I'm not getting voltage out of the relay I may try this. But here's my concern: It's still not clear how the fuel pressure is regulated on this engine. Some sources say there's a separate regulator, but some other sources say that the PCM regulates pressure by varying the fuel pump speed. If there's a separate regulator I can see where it would be OK to jumper the relay. But if the PCM is regulating pressure by turning the fuel pump on and off it's not clear to me it would be OK to override this function.
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PCM uses several inputs to decide if pump runs: If engine speed <~400 RPM it shuts off, for example. PCM grounds terminal "85" to close relay, you should have +12V at terminal "86" all the time (or at least with ignition on).
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Again, this is exactly the kind of info I am looking for. Where are you getting this from? Is it from your Windstar manual?