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Discussion Starter · #1 ·
Car is a 2002 taurus SE vulcan - not flex fuel

I'm trying to drain the fuel tank and shorted pin 3 and 5 of the fuel pump relay and it does not start the fuel pump. According to the connector pinout from the 2002 ford factory service manual, pin 5 of the fuel pump relay is "Fuel pump, Power" and pin 3 is "voltage supplied at all times". I verified 12V at pin 3 with a meter and continuity from the ground pin #2 to the battery negative post. Why doesn't the fuel pump run when I short pins 3 and 5??? I also ran a wire from the battery positive terminal to pin 5 but that did not work. The wire I'm using is 16 gauge. What am I doing wrong?

I know it's the correct relay location. When I take it out and turn the key, nothing happens. I install the relay and turn the key and the pump runs for a few seconds.
 

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According to my 05 wiring diagram, there is something called Fuel Pump Driver Module between fuel pump relay and the pump. What you did (shorting relay pin 3 to pin 5) gives 12V to FPDM, not to the fuel pump. FPDM needs duty cycle command from PCM to run the fuel pump (how long and how often, I suppose). If you need to run the fuel pump to drain the fuel tank, you need to bypass FPDM and hot wire the pump directly at the fuel pump connector. Be careful not to spark near fuel.
 

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Last time I drained a tank I used the fuel pressure test port.
Hooked up a line to a can and let it idle while the pump drained the tank.
That was when I had to change my tank, pump got changed at the same time so I ran it dry without worry.
Otherwise it's siphon time
 

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Car is a 2002 taurus SE vulcan - not flex fuel

I'm trying to drain the fuel tank and shorted pin 3 and 5 of the fuel pump relay and it does not start the fuel pump. According to the connector pinout from the 2002 ford factory service manual, pin 5 of the fuel pump relay is "Fuel pump, Power" and pin 3 is "voltage supplied at all times". I verified 12V at pin 3 with a meter and continuity from the ground pin #2 to the battery negative post. Why doesn't the fuel pump run when I short pins 3 and 5??? I also ran a wire from the battery positive terminal to pin 5 but that did not work. The wire I'm using is 16 gauge. What am I doing wrong?

I know it's the correct relay location. When I take it out and turn the key, nothing happens. I install the relay and turn the key and the pump runs for a few seconds.
I hot wired with a portable battery/jumper. Used the inertia switch and unplugged the wire to the pump and jumpered to that and grounded to the body. I unplugged the line output from the fuel filter and put a hose on that and into a portable gas tank.

-chart-
 

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Discussion Starter · #6 ·
Thanks paker and repairman. I had read somewhere on here that you could hot wire the the relay to get the pump to run but that must have been for an older model taurus. I looked at the diagram and I see where there is the fuel pump driver module inline before the pump. The fuel pump connector isn't in a good accessible location to hot wire.

Repairman, I'm also curious about how long it took you to drain the tank. I could use my pressure tester to do it like you did but the fuel release tube on the tester is very thin. I only have a little less than 1/4 tank so I guess it won't take too long.

I hate it when you think part of a repair is going to be so simple and quick and it turns out not to be!
 

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Discussion Starter · #7 ·
I hot wired with a portable battery/jumper. Used the inertia switch and unplugged the wire to the pump and jumpered to that and grounded to the body. I unplugged the line output from the fuel filter and put a hose on that and into a portable gas tank.

-chart-
Did you use that method on an 01 or 03 sable or a different car? On my diagram, it looks like the inertia switch goes to the fuel pump driver module. If so, I don't think that would work for me.
 

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Thanks paker and repairman. I had read somewhere on here that you could hot wire the the relay to get the pump to run but that must have been for an older model taurus. I looked at the diagram and I see where there is the fuel pump driver module inline before the pump. The fuel pump connector isn't in a good accessible location to hot wire.

Repairman, I'm also curious about how long it took you to drain the tank. I could use my pressure tester to do it like you did but the fuel release tube on the tester is very thin. I only have a little less than 1/4 tank so I guess it won't take too long.

I hate it when you think part of a repair is going to be so simple and quick and it turns out not to be!
That's exactly how I drained mine, small vise grip to hold the release button down.
Took a little while but while it was draining I jacked the car and got set up for the job while it was draining out. I had it below a 1/4 when I started the process.
 

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Did you use that method on an 01 or 03 sable or a different car? On my diagram, it looks like the inertia switch goes to the fuel pump driver module. If so, I don't think that would work for me.
OK I did that on '95. My '01 does not ahve a fuel pump dirver module but my '03 does. I believe the '01 was the last year without. It does not have a pressure sensor on the fuel rail. It has oddball fuel filter with a semi return system while later years do not use any return system.

So that is what I "think" I know.

-chart-
 

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Discussion Starter · #10 ·
I used repairman's method. It took 1.5 hours to drain it/burn it off (15 minutes after the low fuel light came on). This was the best method for me since I did this in the garage and wanted as few fumes as possible. I bought a long tube to connect to the pressure gauge tube so that it would drain into the gas can outside.

Thanks repairman!
 

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That's exactly how I drained mine, small vise grip to hold the release button down.
Took a little while but while it was draining I jacked the car and got set up for the job while it was draining out. I had it below a 1/4 when I started the process.
So what if you do not have a 'shrader valve'.

My '03 does not. It has a pressure transducer where the valve use to go.

-chart-
 

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So what if you do not have a 'shrader valve'.

My '03 does not. It has a pressure transducer where the valve use to go.

-chart-
How do you check fuel pressure? Via scan tool through the transducer.
If so then it's siphon the tank or pump out by disconnecting the fuel filter & attaching a hose to the line or filter outlet.
 

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If so then it's siphon the tank or pump out by disconnecting the fuel filter & attaching a hose to the line or filter outlet.
Good luck siphoning it. Check ball in the fill tube makes siphoning impossible in most newer cars.
 
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