• Mustang Forums
  • 1979 - 1995 (Fox, SN95.0, & 2.3L) -General/Talk-
  • Fox 5.0 Mustang Tech

Could my Fuel pump be on it's way out?

  • Thread starter Thread starter Haus
  • Start date Start date May 23, 2009
H

Haus

Member
Jul 20, 2005
408
0
16
May 23, 2009
#1
  • May 23, 2009
  • #1
I've been having intermittent problems with my power out put with my 92 5.0

feels like its starving for fuel at times. especially when the tank gets below a 1/4 of a tank. once in a while it will make the sound you hear when you run out of gas.

Could the fuel pump be sucking in air and into the fuel lines and making my FP low and leaning out??

FYI my filler neck grommet is shot(doesnt leak but reeks of fuel inside my car when i get more then 1/2 a tank of gas) so could that be allowing air into the tank and causing my fuel pump to suck in air if this is the case.
 

7upstang91

10 Year Member
May 30, 2008
936
124
74
Florida
May 23, 2009
#2
  • May 23, 2009
  • #2
mine does the same thing when i get below 1/4 of a tank. its been doing it for about a year and a half so I'm now worried. I'm just going to upgraded it anyway.
 

2000xp8

SN Certified Technician
Aug 8, 2003
8,029
1,620
194
NJ
May 23, 2009
#3
  • May 23, 2009
  • #3
If it happens more when you are corning or accelerating (when the weight of the car shifts) if could be the tub inside the tank.
I had a tub break loose in mine, so if i was low on gas and stepped on it or tore around a corner the car would starve itself.
Only cure was a nother tank.

If you aren't familar with the tub, it's a thing that looks like a bath tub that the fuel pump sock sits in, so does the filler neck, so when you put gas in the car it's the first place to get fuel, and the last place to have any left.
It's welded to the bottom of the tank and can break loose.

Now, realistically if you think this is the problem, you might as well change the pump too while you are at it.
 
H

Haus

Member
Jul 20, 2005
408
0
16
May 24, 2009
#4
  • May 24, 2009
  • #4
well the fuel pump is 3 years old so i wouldnt replace it unless i had to.

i feel the hesitation and studdering at lower RPM's( around 1000) when i have about a 1/4 tank left. when i step on it, it's fine for the most part

i got to change the grommet so ill take out the tank and check everything out.

when i hear the pump cavitating and is sucking air in the fuel lines is when i start to have problems.

but if i would stop somewhere, turn of my car, then go to start it again and prime the pump its fine for a mile or so then does it again.
 

ID89GT

10 Year Member
May 26, 2008
1,659
18
49
Spokane Valley, WA
May 24, 2009
#5
  • May 24, 2009
  • #5
Is your fuel pump extremely loud? I know my filler neck grommet is shot because when I fill it it leaks out, and my fuel pump is superrrrr loud. I can hear it standing like ten feet away from the car.. All I've done is put in a walbro 255 pump in and the thing is so loud.
 
H

Haus

Member
Jul 20, 2005
408
0
16
May 27, 2009
#6
  • May 27, 2009
  • #6
no its not loud.

if i remember right it started doing this right around the time i replaced the fuel filter
 
You must log in or register to reply here.

Similar threads

F
Difference between 83-86 EFI and 87-97 gas tanks?
  • ForeverDrivin
  • Mar 30, 2026
  • 1979 - 1995 (Fox, SN95.0, & 2.3L) -General/Talk-
Replies
5
Views
273
1979 - 1995 (Fox, SN95.0, & 2.3L) -General/Talk- Mar 30, 2026
ForeverDrivin
F
D
Fox 88 foxbody no power to red and black wire at fuel pump relay
  • drod88
  • Dec 1, 2025
  • 1979 - 1995 (Fox, SN95.0, & 2.3L) -General/Talk-
Replies
7
Views
346
1979 - 1995 (Fox, SN95.0, & 2.3L) -General/Talk- Dec 2, 2025
Mcmahst
F
2004 Mustang GT – Fuel Pump Not Priming
  • Fayio
  • Apr 22, 2026
  • SN95 4.6L Mustang Tech
Replies
7
Views
307
SN95 4.6L Mustang Tech Apr 27, 2026
n0v8or
N
H
Fuel starvation issues, 91 EFI to carb swap. Car dying after 1-3 gallons used. EFI tank, electric fuel pump, bypass regulator. Dual fed carb
  • hassler
  • Oct 11, 2025
  • 1979 - 1995 (Fox, SN95.0, & 2.3L) -General/Talk-
Replies
8
Views
776
1979 - 1995 (Fox, SN95.0, & 2.3L) -General/Talk- Oct 12, 2025
nickyb
B
'03 GT Fuel Pump/Pressure/Delivery Issue
  • Brodach
  • Oct 21, 2025
  • SN95 4.6L Mustang Tech
Replies
8
Views
912
SN95 4.6L Mustang Tech Oct 31, 2025
gkomo
Share:
Bluesky Email Share Link
  • Mustang Forums
  • 1979 - 1995 (Fox, SN95.0, & 2.3L) -General/Talk-
  • Fox 5.0 Mustang Tech
Menu
Log in

Register

  • Forums
  • What's new
  • Media
  • Resources
  • Contact
  • Sponsor
X

Privacy & Transparency

We use cookies and similar technologies for the following purposes:

  • Personalized ads and content
  • Content measurement and audience insights

Do you accept cookies and these technologies?

X

Privacy & Transparency

We use cookies and similar technologies for the following purposes:

  • Personalized ads and content
  • Content measurement and audience insights

Do you accept cookies and these technologies?