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Help, Mustang Not Starting (Fuel Pump Issue?)

  • Thread starter Thread starter CoolFool99
  • Start date Start date May 25, 2023
C

CoolFool99

New Member
May 25, 2023
1
0
1
May 25, 2023
#1
  • May 25, 2023
  • #1
Hello,

I have a 2003 Mustang GT Auto, it’s been sitting for about a year, tried to start it but the battery was low/dead, it did start for a few seconds but then died, I think the gas might be bad, I did fire it up about a couple months ago, it ran but was just struggling with the bad fuel.

Tried to jump start it and it’s not getting any fuel, I disconnected the fuel line at the engine and no fuel is being pumped, nor can I hear the pump when the key is in run, the fuse is okay for the fuel pump. I also checked the inertia switch and the button is down.

When in run, the theft light turns off but the service engine soon light is on, I connected my code reader but it says there are no active codes.

What is the problem?

I heard there might be some sort of relay/module soldered in the wheel well of the passenger side or a different fuel module in the trunk? How do I go about checking those? Or should I be checking something else first? Or is there an easy way to see what is wrong?
 
G

Gtstangman

Member
Apr 13, 2019
3
3
13
denver
May 29, 2023
#2
  • May 29, 2023
  • #2
CoolFool99 said:
Hello,

I have a 2003 Mustang GT Auto, it’s been sitting for about a year, tried to start it but the battery was low/dead, it did start for a few seconds but then died, I think the gas might be bad, I did fire it up about a couple months ago, it ran but was just struggling with the bad fuel.

Tried to jump start it and it’s not getting any fuel, I disconnected the fuel line at the engine and no fuel is being pumped, nor can I hear the pump when the key is in run, the fuse is okay for the fuel pump. I also checked the inertia switch and the button is down.

When in run, the theft light turns off but the service engine soon light is on, I connected my code reader but it says there are no active codes.

What is the problem?

I heard there might be some sort of relay/module soldered in the wheel well of the passenger side or a different fuel module in the trunk? How do I go about checking those? Or should I be checking something else first? Or is there an easy way to see what is wrong?
Click to expand...
If the pump hasn't been replaced to your knowledge I guess I would just Install a new pump. Most likely it has seized if you don't hear it and It's not pumping fuel. Based on it's age you would have the peace of mind it won't leave you stranded as well with a new pump on board.
 
Y

Yel2002GTAuto

Active Member
Sep 26, 2022
233
26
38
Granit City, IL
Jun 1, 2023
#3
  • Jun 1, 2023
  • #3
There are a couple things to try....

1st - It could be bad fuel but unlikely...unless the car sat for 7 plus years it should be ok... but you would have to drop the tank to drain it ...

2nd - I would check the Fuel Filter.... only takes 10 mins to replace and is a cheap fix... those can go bad if old and sitting for a while...

3rd - there is a switch in the trunk on the driver side behind the rear tail light area, check to see if that has tripped...

4th - Check fuses under the dash and in engine bay.... can easily locate diagrams online for locations of fuses...

5th - Last would be to change out the fuel pump..... not a hard job...probably 2 hours to raise the rear up, drop the tank a bit and take off the top hat and pull out/switch the fuel pump....

Ed
 

dochawk

Member
Apr 12, 2023
38
2
8
Jun 1, 2023
#4
  • Jun 1, 2023
  • #4
Yel2002GTAuto said:
3rd - there is a switch in the trunk on the driver side behind the rear tail light area, check to see if that has tripped...
Click to expand...

I came to mention this one. It apparently caused a great many of my problems, leaving the car to sit idle for a couple of years, then needing even more repairs.

You need to pull the carpet panelling off at the driver fender by the taillight.

there will be a black box with a red button.

in normal operation, that button should be all the way in. When something goes wrong, it pops out a bit.

harbor freight has a plastic body tool kt that can pull the black plastic pins without breaking them (among its other tricks) for about $6.
 
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