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Discussion Starter #1
Hi everyone,

I have a 97 Taurus with a 3.0 Vulcan. I spent the last three months rebuilding the engine because it had high miles and a really bad oil leak at multiple cylinders. That's out of the way and I went to crank it on, but it is getting zero fuel pressure.

I checked the CCRM and it seems to operate just fine. Resistance across the FPR solenoid is 76 ohms. I have not tried to trigger the FPR solenoid with 12 volts and check for continuity on the high side. I get 12+ volts at the fuel pump fuse, 12+ volts at the CCRM connector. This is where it gets interesting/confusing. I set my multimeter on the inlet side of the fuel cut off switch plug and send the other probe to the ground connection in the trunk. With the multimeter set to capture a max reading, I get 12+ volts when I turn the key to 'ON'. When I take it off max reading mode, it settles out somewhere in the 6.8 to 7.0 volts range after the ignition is in the 'ON' setting for a few seconds.

I've already replaced the fuel filter so I can't imagine that even if the pump were humming that there would be any restrictions.

Needless to say, I don't hear the characteristic hum of the fuel pump. I check the fuel pressure at the manifold and there's nothing there. Its certain the pump isn't running, but I'm stumped on the cause. Is it possible the relay is somehow weak and only allowing so much voltage get across the high side terminals? Maybe the FPR solenoid is weak and not fully contacting the high side terminals? I was reading another post where someone suggested smacking the bottom of the fuel tank with a wooden stick to somehow revive the pump. Any thoughts on that approach?

Thanks, - Troy
 

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NEVER use a DMM to check power circuits!!! Use a test light that will draw some decent current. Due to the 11 million ohm input resistance of a DMM it will indicate system volts even if there is high resistance in the circuit.

I use an old 1056 backup light bulb with alligator clip leads soldered to the bulb terminals that will draw around 2 A at 12 V.
 

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Discussion Starter #4
Thanks for the responses. Based on the feedback, I've gone ahead and opened up the CCRM to test it. I put 12 volts to the fuel pump relay and I get perfect continuity across the leads. I get a solid 12 volts at the fuel pump fuse and leading up to pin 5 of the CCRM. The only thing I can I think at this point is that there is somehow a fault in the wiring leading up to fuel cutoff switch.

Does anyone know if this particular model is known for a weak point in the wiring harness that's susceptible to corrosion? That's the only thing I can think of that would cause a short that might rob power at the cutoff switch.

Otherwise, I'm just stumped on this one. I've gone ahead and pulled the wiring harness from the fuel pump pig-tail. Next chance I get I'll work out a way to put 12 V straight to the fuel pump. Its kind of sad you have to drop the fuel tank to get access to the pump. I was hoping there'd be access from under the rear bench like on other cars.

-Troy
 
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