fuel pump problems

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Nov 11, 2004 | 04:57 PM

mrcarter

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fuel pump problems

I have an 87b2, 4wd, 2.9v6. I'm having some electrical problems. I'm not sure whats going on. I have 2 fuel pumps, one low-pressure, in-tank pump and an in-line, high-pressure pump. For some reason there is no power getting to the high pressure pump and i dont even know if there is any power getting to the low-pressure pump. Everything is normal when i turn the key, just no fuel. I've been staring at wiring diagrams for three days now and I can figure out whats going on. There is no fuse for the pump and i havent been able to find any fusable links.

Nov 11, 2004 | 05:43 PM

mrshorty

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From: UT

Three days of staring at wiring diagrams and you can't figure it out. I feel your pain. Let me see if I can help.

Fuel pump circuit is pretty much a basic DC circuit, and I'm going to assume you understand basic DC electronics. Circuit should look like this (verify against your wiring diagram) B+, fusible link R (on these engines, fusible are simply wires that are a gauge or two smaller than the normal wire for that circuit), fuel pump relay (controlled by computer), inertia switch, fuel pumps (in parallel, I believe), B-. Basically, you need to put your voltmeter across the circuit at various places and determine where you have power and where you don't.

Nov 12, 2004 | 08:45 AM

cokoliso

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Have you checked the inertia switch? Seems like the simplest explanation.

Nov 12, 2004 | 08:48 AM

cokoliso

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Easy to check the inertia switch - there is a compartment on the wall behind the driver's seat. For the other stuff you need a test light or a meter. Ground one lead and probe the power wire to the fuel pump, and work backwards to the relay.

Nov 13, 2004 | 10:55 PM

wolffpax

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There is a fusible link located at the starter solenoid. I had mine blow and it gave the same symptom.

Nov 14, 2004 | 09:51 PM

mrcarter

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its not the inertia switch, i wish it was...and ive checked the fusible links at the starter solenoid and those arent it either.

Nov 15, 2004 | 02:44 AM

onestrangebroncoII

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From: crossville tn

my 86 has a fuel interupter gadget down in the floor board on the passenger side that finally melted its a balck box about the size of a pack of cigarettes with a white button to reset the damn thing. i just pulled the two wires out of that melted piece of turd and twisted them together and taped them up and everthing works fine

if this does not work can ya run a ghetto wire from the battery to your fuel pumps and get em flowing again?

...

i hate wires!!!!!!!pass the tape please

when i do my v8 swap i am getting rid all that crap i want like three wires that are not spark plug related and a nasa car style steel dash with gauges and a couple of switches no keys or nothin then i will sell all my junk my ebay