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  • 1996 - 2004 SN95 Mustang -General/Talk-
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fuel pump not working

  • Thread starter Thread starter pyro99
  • Start date Start date Mar 10, 2010
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pyro99

New Member
Mar 6, 2010
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Mar 10, 2010
#1
  • Mar 10, 2010
  • #1
i have a 2000 gt. i just swapped out the motor with a junk yard one because it was blown.for some reason the fuel pump does not seem to be kicking on. i changed the pump i changed the fuel pump drive modulator and still nothing. it has an aftermarket viper alarm. not sure if this could be the problem. i cant locate the PCM. might i need to change that? i really feel like this is a computer issue of some sorts. any help would be great.
 

wmburns

SN Certified Technician
Aug 14, 2009
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Houston Texas
Mar 10, 2010
#2
  • Mar 10, 2010
  • #2
Check the IFS switch in the trunk.

Are all of the fuses good?

What is the theft light doing?

Did you re-connect all of the smaller connectors under the battery and under the intake tube?

Do you hear the fuel pump run for a few seconds when the key is cycled on/off (do not start)?

On the 1999-2004 PATS will disable fuel and spark. This results in a crank with no-start.

Suggest checking the aftermarket alarm.

Have you confimred spark?
 
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pyro99

New Member
Mar 6, 2010
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Mar 11, 2010
#3
  • Mar 11, 2010
  • #3
the ifs is good. i tripped it and reset it. i have spark if i spray fuel into the intake it will run. the theft light blinks kind of rapidly. i have waited the the 15 minute time period and still nothing. when i cycle the key on and off i do not hear the fuel pump. i checked volatge and i have 6.7 volts at the fuel pump control driver module and 10.5 at the pump in the tank. everything is hooked up and double checked. all fuses are good. could the PCM be bad? where is this located at in the car. and what is the PATS you speak of.
 

wmburns

SN Certified Technician
Aug 14, 2009
5,892
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Houston Texas
Mar 11, 2010
#4
  • Mar 11, 2010
  • #4
Check PATS

PATS equals the theft system. The terms are interchangable.

If you are measuring 10.5 volts at the pump itself AND the pump is not running, then the pump is bad.

However, I tend to question the results of this test. On the 1999-2004, the PCM/FPRM does not power the pump to run for very long with the engine off. So unless you performed the test while cycling the key, it is doubtful that you are actually measuring power to pump.

However, if the theft light is flashing, that usually indicates the PATS system has been tripped or a PATS related problem.

Suggest that you double check your work. Esp since you already have installed a new fuel pump. IMO, it is important to determine if the PATS system has been tripped or this is just a bad fuel pump.

Exactly what is the theft light doing?

>>>From Ford service CD
PATS uses a visual theft indicator. This indicator will prove out for three seconds when the ignition switch is turned to RUN or START under normal operation. If there is a PATS problem, this indicator will either flash rapidly or glow steadily (for more than three seconds) when the ignition switch is turned to RUN or START. PATS also "blips" the theft indicator every two seconds at ignition OFF to act as a visual theft deterrent.
 

trombonedemon

Well-Known Member
Jun 25, 2009
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U.S.A, U.S.A., U.S.A.!
Mar 11, 2010
#5
  • Mar 11, 2010
  • #5
Bench test the pump to see if the pump is working, as Burns might tell you, you can bypass the Pats system!
 

Alex46

New Member
Feb 19, 2010
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Mar 12, 2010
#6
  • Mar 12, 2010
  • #6
Do the SN95 have that fuel pump relay in the trunk like the 5.0? That was a great relay
 

wmburns

SN Certified Technician
Aug 14, 2009
5,892
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Houston Texas
Mar 12, 2010
#7
  • Mar 12, 2010
  • #7
Fuel pump power controled by the Constant Control Relay Module (CCRM). The CCRM is in the right hand fender well engine bay.

There is an Inertial Fuel Shutoff (IFS) switch in the trunk. The switch is designed to cut off power to the fuel pump in the event of a crash. The OP has already reported testing the IFS as good.
 
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