Wiring to Fuel Pump
chitown
08-15-2005, 12:53 PM
I have a 91 TC. Sometimes I can hear what I think is the fuel pump. The sound seems to be coming from under the Driver side door, but I thought the fuel pump was in the tank. I need to check and see if I have wiring going to the fuel pump. Is there a diagram I use to help with this?
Towncar
08-15-2005, 02:04 PM
I have a 91 TC. Sometimes I can hear what I think is the fuel pump. The sound seems to be coming from under the Driver side door, but I thought the fuel pump was in the tank. I need to check and see if I have wiring going to the fuel pump. Is there a diagram I use to help with this?
Well, I have a 96 manual. I don't know much about the difference between 91 and 96 so I'll shut up.
As for the "noise" that sounds like a pump near the drivers door, that could be only one of two possibilities.
If you have ABS, it could be the ABS pump firing up just under the power brake booster.
More likely, it's the rear air-spring compressor pumping air into the rear air-springs. The compressor is located just under the Intake Airbox on the left-front fender well. The noise reverberates all over the place, to an untrained ear it may seem to be sounding from somewhere else.
Yes, your fuelpump is in the tank.
Well, I have a 96 manual. I don't know much about the difference between 91 and 96 so I'll shut up.
As for the "noise" that sounds like a pump near the drivers door, that could be only one of two possibilities.
If you have ABS, it could be the ABS pump firing up just under the power brake booster.
More likely, it's the rear air-spring compressor pumping air into the rear air-springs. The compressor is located just under the Intake Airbox on the left-front fender well. The noise reverberates all over the place, to an untrained ear it may seem to be sounding from somewhere else.
Yes, your fuelpump is in the tank.
chitown
08-15-2005, 04:24 PM
Well, my car will crank, but just won't turn over. When I turn the ignition, I don't hear anything coming from the tank. Meaning, I don't hear the fuel pump. I read somewhere that it could be the ground at the battery. Is there any truth to this or maybe it could something else?
Well, I have a 96 manual. I don't know much about the difference between 91 and 96 so I'll shut up.
As for the "noise" that sounds like a pump near the drivers door, that could be only one of two possibilities.
If you have ABS, it could be the ABS pump firing up just under the power brake booster.
More likely, it's the rear air-spring compressor pumping air into the rear air-springs. The compressor is located just under the Intake Airbox on the left-front fender well. The noise reverberates all over the place, to an untrained ear it may seem to be sounding from somewhere else.
Yes, your fuelpump is in the tank.
Well, I have a 96 manual. I don't know much about the difference between 91 and 96 so I'll shut up.
As for the "noise" that sounds like a pump near the drivers door, that could be only one of two possibilities.
If you have ABS, it could be the ABS pump firing up just under the power brake booster.
More likely, it's the rear air-spring compressor pumping air into the rear air-springs. The compressor is located just under the Intake Airbox on the left-front fender well. The noise reverberates all over the place, to an untrained ear it may seem to be sounding from somewhere else.
Yes, your fuelpump is in the tank.
Towncar
08-15-2005, 05:59 PM
..When I turn the ignition, I don't hear anything coming from the tank. Meaning, I don't hear the fuel pump. I read somewhere that it could be the ground at the battery. Is there any truth to this or maybe it could something else?
You may also be interested in this thread... (http://www.lincolnsonline.com/cgi-bin/ultimatebb.cgi?ubb=get_topic&f=3&t=004479)
It's possible you wont hear the fuel pump, especially if the pressure is already up to spec in the fuel rail.
To rule out fuel delivery as a suspect, you need to evaluate the fuel pressure at the fuel rail. There's a test port (schrader valve) located somewhere on the fuel rail. Normally you'll attach a fuel pressure guage here, and read the rail pressure, compare that to the required spec.
However, you can jerry-rig an attachment of your own concocktion just to see if there appears to be sufficient fuel present in the rails to start the car. With the key on the rail is fully pressureized, be careful.
(see #1 in the diagram attached for a sample of fuel-rail schrader valve)
http://www.ftpp.net/Temporary/1995-2002%203800%20Fuel%20Rail.jpg
If you suspect any grounds, by all means clean them up too.
The fuel pump wire-head (if you're interested in testing voltage there) may be accessable through a trap-door under the trunk carpeting, most are.
You may also be interested in this thread... (http://www.lincolnsonline.com/cgi-bin/ultimatebb.cgi?ubb=get_topic&f=3&t=004479)
It's possible you wont hear the fuel pump, especially if the pressure is already up to spec in the fuel rail.
To rule out fuel delivery as a suspect, you need to evaluate the fuel pressure at the fuel rail. There's a test port (schrader valve) located somewhere on the fuel rail. Normally you'll attach a fuel pressure guage here, and read the rail pressure, compare that to the required spec.
However, you can jerry-rig an attachment of your own concocktion just to see if there appears to be sufficient fuel present in the rails to start the car. With the key on the rail is fully pressureized, be careful.
(see #1 in the diagram attached for a sample of fuel-rail schrader valve)
http://www.ftpp.net/Temporary/1995-2002%203800%20Fuel%20Rail.jpg
If you suspect any grounds, by all means clean them up too.
The fuel pump wire-head (if you're interested in testing voltage there) may be accessable through a trap-door under the trunk carpeting, most are.
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