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1991 Mustang Gt Fuel pump will not turn on or prime

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Old 07-03-2012, 04:09 PM
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lavertue
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Default 1991 Mustang Gt Fuel pump will not turn on or prime

So after driving my car for a few hours yesterday, i stopped put gas in my car and drove home. I parked the car for a few hours. I then disconnected my battery so i could hook up my car audio. When I put the battery back on I tried starting it and nothing. I checked my fuse under the dash and it looked fine but i replaced it anyways. I dropped my tank and i went and got a brand new fuel pump. Well before i put the tank back in i figured id try to see if it would run, and no luck. So now i am stuck. I checeked my inertia switch in my trunk and it was still pressed down. I have no changed my relay because I heard those rarely go bad. If anyone has any input it would help greatly. My car is sitting in my drive way with the tank on the ground right now. Thanks in advance.
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Old 07-03-2012, 04:15 PM
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Derf00
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all other electrical stuff working ok on the car?

When you disconnected the battery did you disconnect negative first, then positive? When you reconnected the battery did you connect positive first, then negative?
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Old 07-03-2012, 04:17 PM
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van-swink85
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To check a relay i believe if it rattles then its bad if i were you i would go ahead and replace itbecause its obviously not making a connection somewhere. So start with relays and fuses. If it dont work then someone else that knows more will eventually chime in
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Old 07-03-2012, 04:22 PM
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Dj_Seph
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All that and you didn't think of the first thing? Fuel pump relay. It's under your seat. You probably disconnected it doing the wiring for your audio.

Relay controls if it comes on and primes. That's most likely what it is...
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Old 07-03-2012, 04:36 PM
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lavertue
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I'm going to pick up a new relay right now. I guess i shouldn't have ruled that out..
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Old 07-03-2012, 05:56 PM
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Picked up a new relay, and still nothing. No priming.
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Old 07-03-2012, 06:13 PM
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TrimDrip
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Here is a diagram. There are several fuse links that could have blown. The red wire will only be hot while the pcm relay is throwing power to it. So you will have to check it right after the key is turned on. Or just pull the kick panel and check the wires at the pcm relay.

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Old 07-04-2012, 08:26 PM
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Js88lx
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OK..., check the emrgency switch that is in your trunk inbetween the back panel behind the drivers taillight!! It has a little button facing up, make sure you push down on it.., happened to me a while back, figured it ou after i change fuel pump,,, DUH!! Just check that b-4 anything!!
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