Fox T-Bird/Cougar Forums

what about the possibility of a short in the circuit or a faulty/intermittent ground issue putting strain on the fuel pump motor.

Try bench testing one of your pumps that you pulled out. Apply power and ground to the appropriate terminals and see if it runs. A few seconds without it in the tank drawing fuel won't hurt it and since you said they weren't running at all this would tell you if it is the pump or wiring.

I also second the wiring issue, perhaps check your fuses.  I just ran through a similar issue on my Volvo...a bad/old/corroded fuse was causing the intank to cut out.

A short in the wiring would keep it from running if it was an open short. I was thinking more along the lines of a hot short to ground where the pump was still getting voltage but not enough to operate properly. I have seen it before in particular on the last generation of Chevy Caprices where the green(power feed) wire runs under the back seat on those cars and gets pinched from passengers and starts a short to ground but not enough to stop it from working. I spent several days tracking down that problem but when I found it I was able to stop replacing pumps(they weren't the problem). The feed wire was. Just a thought. I am not as familiar with these cars yet as I would like to be or as most of you are but I am working on it.

@speedemon(don't give up on me, I appreciate any help)...allright, my son and I checked the power going to the pump(right at the pump plug), checked with the old trusty 12v light thingy(got power for the first 2-3 sec, prime time).
  We then checked the voltage (key on) with a volt meter and got a .30 reading?? is this right?? we checked all the wires going to the pump and they all LOOK in great shape, they aren't cracked, broke, or even fragile at all, the underneath is very clean. I did notice when we took the pump out that the plug going right into the pump itself wasn't all the way locked, pushed it in and still nothing. Took the pump out and bench tested and she was DEAD!!
  @jcassity,,,,I will try all your info tomorrow(thanks for your help, you are the electro man!!), I did try probing the pump ralay(yellow wire) the other day with a 12v light(watchamacallit)and there was consant power, but i didn't check the voltage, I will try this tomorrow also(should it be 12????volts??)
  It just seems funny that i never had this problem untill my son and I put in the (1st) new pump, the tank has never been down before this(as far as i know).

Thanks again guys for all the help so far, i REALLY want to drive this thing again,like NOW!!!!!

@speedemon(don't give up on me, I appreciate any help)...allright, my son and I checked the power going to the pump(right at the pump plug), checked with the old trusty 12v light thingy(got power for the first 2-3 sec, prime time).
  We then checked the voltage (key on) with a volt meter and got a .30 reading?? is this right?? we checked all the wires going to the pump and they all LOOK in great shape, they aren't cracked, broke, or even fragile at all, the underneath is very clean. I did notice when we took the pump out that the plug going right into the pump itself wasn't all the way locked, pushed it in and still nothing. Took the pump out and bench tested and she was DEAD!!
  @jcassity,,,,I will try all your info tomorrow(thanks for your help, you are the electro man!!), I did try probing the pump ralay(yellow wire) the other day with a 12v light(watchamacallit)and there was consant power, but i didn't check the voltage, I will try this tomorrow also(should it be 12????volts??)
  It just seems funny that i never had this problem untill my son and I put in the (1st) new pump, the tank has never been down before this(as far as i know).

Thanks again guys for all the help so far, i REALLY want to drive this thing again,like NOW!!!!!

you forgot to do one thing,, you forgot to make the pump run full time and thats why you got no power or .3v for a reading.  the ground to the fuel pump relay was removed by the eec at 3-5sec.

Yes I did forget to do this and I will try again

now go back with a jumper wire and do the full time test.  once that is done, you can test.

as for the power and your asking if it should be 12v.....?
Not once did i mention 12 volts.  I said that your reading on the yellow wire at the starter solenoid will be your "standard" or your reference voltage.

I gotcha on this one and I will also check this reading and go from there. which i take it that whatever that reading is(at the starter selonoid) my readings at the pump shoul read the same??


speeddemon-
he said he checked with a volt meter,, and judging from he exact reference to a .30v its highly unlikely anyone would be able to interpert an buttstuffog meter reading to that level of exactness unless like you said, he was set on the DCVx1 scale.

my meter is an older Tenma digital meter and I had it set on volt/DC when I took my reading which was right at the plug that hooks into the pump. I am not really top notch when it comes to what to set my meter on and reading these meters but i will give it my best when i have you electrical gurus to show me.

Thanks guys

.

I gotcha on this one and I will also check this reading and go from there. which i take it that whatever that reading is(at the starter selonoid) my readings at the pump shoul read the same??

make sure no power exists on the tan/light green wire,,,,where(pump relay?, at the self test/ without ground?/or with?)---- also how do i check for resistance from the tan/light green to frame?(what shoud i set my meter on for a resistance reading)??

Thanks so much for all the help, Joe

actually , the more i think about it the more i realize my fingers got ahead of my brain on that one.  If you check for power on the tan light green wire to ground, your just going to run your pump full time.  its the same point electrically as the eec self test conn where you pull codes.



So if you pulled your readings with the tan light green grounded out, it appears all is well with power delivery of your fuel pump circuit.

Did the pump run with the Key on and the TAN/ LightGreen wire grounded ?
You can ground this wire back at the fuel pump relay also just by probing it with a stick pin and gator clip it to chassis ground or........ ground it up at the eec self test conn.

If your are able to get the pump to run with the tan light green grounded at the fuel pump relay but not at the eec self test connector, then the wire is broken either up at the eec self test path or more likely the path leading up to the EEC.

Your first complaint was you could not hear the pump prime at all,, did you hear it run?