No fuel pump voltage

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Dec 27, 2005 | 06:01 PM

jrupert3

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No fuel pump voltage

hello every one, this is my first post here

I have a 1986 Bronco ll, 2.9 fuel injected. It stopped running last week had towed to a garage who told me both fuel pumps are dead at the same time ??, they wanted $2000.00 to repair. Put a volt meter on the high pressure pump and had no voltage, the ford trouble shooting guide says to replace the fuel pump relay, and a chat board posting recommends to replace the ecm relay, I purchased both today thinking I can match the new ones to the old ones to figure out which one was which, but to my surprise they all (5) have the same pin configuration, the old ones do not have any identification (worn off long ago) I am looking at the relay that are mounted under the hood on the passenger side. Any ideas to id the correct one’s?The roll over switch is good, I jumpered around it to be sure

Last edited by jrupert3; Dec 27, 2005 at 06:08 PM.

Dec 27, 2005 | 06:29 PM

Ken00

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From: South Jersey

Welcome to FTE!!!

The FP relay is normally green. Great idea holding off on the repair and looking at it yourself.

Dec 27, 2005 | 06:40 PM

97Centurion

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From: Lawrence, KS

Welcome to FTE jrupert3. I would also check the inertia switch. On my 88 it is above where the passanger puts his feet on the fire wall.

Dec 28, 2005 | 11:18 PM

Monty06

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From: miami florida

i pretty sure he jumped over the inertia switch in his words the roll over switch.
like ken says the fp is nomally green right next to that one is your ecm relay.

Dec 29, 2005 | 06:34 AM

jrupert3

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Thanks for the help so far, I changed out the green relay with the new one, after a few cranks, the new relay was smoking. I pulled the high pressure pump and connected it to power directly and it runs, but unable to get power to the pump. so still trouble shooting with out much luck.

Dec 30, 2005 | 04:07 PM

Ken00

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From: South Jersey

Have you tried powering the low pressure pump?

Whats the resistance between the wire at the pump and the connection at the relay?

Dec 30, 2005 | 06:34 PM

rebocardo

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From: Atlanta GA

> garage who told me both fuel pumps are dead at the same time

Very unlikely.

One relay is green, the other brown. Match them by colors when replacing the relays.

If the vehicle died while driving I would suspect the TFI module above all else and start there before you do anything with the fuel pumps. Then I would check the coil and its connectors.

THEN I would start checking the fuel pumps AFTER I changed the fuel filter and checked the inertia switch.

Then I would do a search here for others with fuel pump problems.

Your 86 might have two fuel filters. See if there is a black cannister near your gas tank. Sometimes these came empty from the factory, sometimes they came with a filter. FWIW: The only way to open these cannisters up is in a vise off the vehicle with water pump plyers.