1999 Mustang V6 fuel pump issue

Thair92

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I have a 1999 ford mustang with the V6 3.8 engine. The car has been sitting for years and just started working on it.

The issue I am facing here is that the engine is not getting gas ( checked the through the Schrader valve). When turning the ignition switch to on position, I hear the clicking that is supposed to be the relay, along with a low buzzing, and I think its the pump priming. I am trying to test that power is getting to the pump before dropping the tank and get dirty. I cant seem to find the relay, checked, the fuse box, under the steering wheel, passenger side, and next the inertia switch but couldn't find it. any ideas where else it could be? is it safe to assume that the clicking and buzzing are actually the pump and the relay?
 

PinkieT

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The down and dirty way to see if your fuel pump is working is to disconnect the fuel line at the filter, direct it into a bucket or gas can, and turn on the ignition. I would put on a new fuel filter too.
 

ttocs

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I am not an expert on the v6 but if its like the 8's the power goes to through the floor of the trunk on the passenger side. There are 4 wires, 2 are for the level sender and then 2 are for the pump.
 

Thair92

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@PinkieT @ttocs thanks for your replies will definitely check this. there is also one more thing I wanted to check, I just found out that the fuel pump relay is located inside the CCRM and not separately, and based on the location of it that's where the clicking is coming from. When I turn the switch, I hear the first click, and few seconds later another click and that's it. is that normal?
 

ttocs

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there should be a few relays clicking now if they are to do with the pump takes some testing. Just curious is there an inertia switch in the trunk like on my 94 to shut off the fuel if there is an impact? If so test it for power with the key on.
 

Thair92

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there should be a few relays clicking now if they are to do with the pump takes some testing. Just curious is there an inertia switch in the trunk like on my 94 to shut off the fuel if there is an impact? If so test it for power with the key on.
Yes there is one
 

07GtS197

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Have you tried priming it multiple times before trying to start it? It sounds like the fuel pump is still working, though it could be weak.


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Silver95bird

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First off, I'd replace the fuel filter.
Next, I'd put a fuel pressure guage on the schrader valve, and turn the face so you can see the results through the windshield.
Turn the key a few times and see if it comes up to full pressure, and if it stays up.
 

Thair92

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Have you tried priming it multiple times before trying to start it? It sounds like the fuel pump is still working, though it could be weak.


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Yes I tried to prime it three times and then check the Schrader valve, no fuel came out.
 

Thair92

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First off, I'd replace the fuel filter.
Next, I'd put a fuel pressure guage on the schrader valve, and turn the face so you can see the results through the windshield.
Turn the key a few times and see if it comes up to full pressure, and if it stays up.
I checked the valve after priming the pump for few times, not with a gauge pressure tho, I just pushed the pin to see if fuel would come out but nothing
 

ttocs

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it could be a bad valve though or even a hole in the rubber hose between the pump and the outside of the tank so that the gas just leaks back into the tank taking the pressure away. everyone should have somewhere to look and see their pressure no matter under the hood or in the car. if you do not want to spend the money on a cheap gauge then as then start by checking the voltage before/after the inertia switch. IIRC there are two wires going into it and with the key on they should both show the same voltage. If that is good then go try the filter.
 

95opal

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Failing pump and clogged filter. Disconnect at filter and prime into a bucket. If nothing pump is more than likely shot. Verify 12v at pump also.
Best bet with fuel issues is a pressure gauge on the rail.
 

Thair92

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Thanks, will check. I also thought that if I check the connection just above the tank, unplug it and test all the pins maybe that's enough to indicate if the pump is getting power or not?
 

outdare

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You should hear the pump cycle on when the key is turn on not starting. It will prime the line. Fuel pressure tester can be rented at most auto parts stores. Fyi get a Schrader valve set with tool. If the car is old you may have to replace the test port valve. Schrader valve kit is cheap and if you don't use it return it.

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Randall Garner

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One think I did not see to check is the fuse and relay in the engine compartment. Fuel pump fuse is one of the large maxi fuses and pump relay. Is one of the 2 or 3 relAys for a 3.8.
 

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