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1999 4.6 GT Fuel Pump

  • Thread starter Thread starter 99_2v
  • Start date Start date Nov 12, 2018
9

99_2v

New Member
Nov 12, 2018
1
0
1
Tennessee
Nov 12, 2018
#1
  • Nov 12, 2018
  • #1
My car recently shut off due to a bad fuel pump (I thought). I replaced the fuel pump and realized that it just tripped the shut off switch. Well I drive a lot on the highway for my job, and I was cruising in 5th gear at about 2600-2800 RPMs. I gave it some throttle and it started bogging, I proceeded to turn my hazards on and get on the edge of the highway. The car shut off and wouldn't start again. I checked the fuel pump switch (which i replaced also while I replaced the fuel pump.) the switch was tripped so I turned it back on and it started right up. Drove about 3 miles down the road and it did the same thing. Like I said i've replaced the fuel pump and the fuel pump shut off switch, and it STILL continues to shut off while im in 5th gear driving 60+. Any help or tips are appreciated!
 

wmburns

SN Certified Technician
Aug 14, 2009
5,892
514
204
Houston Texas
Nov 12, 2018
#2
  • Nov 12, 2018
  • #2
IMO you need to consider the possibility that:
  • The IFS is not mounted correctly. IE, too loose or in the wrong orientation
  • There's something inside the trunk that's making contact to the IFS switch
  • There's a large metal object or a magnet near the IFS.
  • the replacement IFS is bad
  • The problem is not related to the IFS switch at all.
In general when a car shuts off for no apparent reason and then is able to be restarted my first thought is "bad alternator or bad battery".

Howto perform charging system voltage drop test
https://www.stangnet.com/mustang-fo...perform-charging-system-voltage-drop-test.56/
 
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