No voltage at fuel pump

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Sep 7, 2004 | 06:26 AM

drmeece

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No voltage at fuel pump

Hi Guys. I have an 87 f150 4.9 with no voltage at the fuel pump...I can hear the relays next to the air cleaner click..I reset the fuel shut off under the dash,or at least I think i did.. I pushed the button down but there was no click like you would hear resetting a breaker...I don't know if that means anything or not..Anyway what else could be the problem...Oh by the way this is the external fuel pump...I can get it to run by running a lead from the batt.Thank you Daryl...

Sep 7, 2004 | 07:28 AM

EPNCSU2006

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From: Concord, NC

Can you tell if the in-tank pumps run? There are two relays near the air filter - one for the computer, and the green one is for the fuel pumps. Just to be sure, I'd take the green one and hold it to feel if it clicks. The fuel pump relay should click off about 2 seconds after you turn the key to run, if you don't crank the engine, so you can listen for that too.

Sep 7, 2004 | 10:39 AM

drmeece

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yes the relay is clicking as you descibed..thank you..

Sep 7, 2004 | 10:51 AM

EPNCSU2006

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From: Concord, NC

I guess now it's just a matter of tracing the power wire checking voltage along the way to see where it stops. I have some wiring diagrams that might help you - they are in my gallery, but are small, so if you need the full size ones, just shoot me an email.

Sep 8, 2004 | 08:25 AM

drmeece

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ok...thank you

Sep 8, 2004 | 05:34 PM

noogie102283

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i dont know about every truck but my 87 150 5.0's shutoff switch gave a good click when i reset

Sep 8, 2004 | 07:42 PM

Saurian

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Joined: Dec 2003

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From: Centerville, Iowa

When you reset the inertia switch, did it remain in the down position? My intertia switch when I went to inspect it, the button was down, so I'm assuming that my intertia switch hasn't been thrown? I'm at a loss.

I'm in the same position as you brother! No voltage at ext fuel pump, relay is good, intertia switch seems alright...