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Engine Fuel not pumping

  • Thread starter Thread starter Creomod
  • Start date Start date Apr 13, 2026
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Creomod

5 Year Member
Sep 14, 2018
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San Antonio,Texas
Apr 16, 2026
#21
  • Apr 16, 2026
  • #21
AeroCoupe said:
What about after the prime and you are cranking the car? Doesn't the ECU need to see a PIP signal to run the pump?
Click to expand...
Yea I belive so I guess I’m gonna swap the pip maybe the pip went bad being in a box I guess we’ll see
 

AeroCoupe

lube between the nut and the face. I know my lubes
Founding Member
Oct 28, 2001
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Apr 16, 2026
#22
  • Apr 16, 2026
  • #22
Before you do that. Pull the distributor and then connect the wiring back up. Turn the key to "run" and then go back under the hood and spin the distributor gear by hand. You should hear the injectors fire and if you do the PIP is good.
 
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Creomod

5 Year Member
Sep 14, 2018
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San Antonio,Texas
Apr 18, 2026
#23
  • Apr 18, 2026
  • #23
Question I’m installing dustbutot and I don’t see the marks with the timming light and it sounds like a truck
 

AeroCoupe

lube between the nut and the face. I know my lubes
Founding Member
Oct 28, 2001
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Apr 18, 2026
#24
  • Apr 18, 2026
  • #24
Guessing you got it stabbed out of time. Probably best to just start over by putting the motor at TDC, stab the dizzy and the rotor should point at the #1 cylinder post on the cap with the distributor fully installed. I install the cap and just make a mark on the adapter (what the cap connects to) where the #1 cylinder post is.

You have to be on the compression stroke or it will be 180 out.
 
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Creomod

5 Year Member
Sep 14, 2018
511
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San Antonio,Texas
Apr 18, 2026
#25
  • Apr 18, 2026
  • #25
AeroCoupe said:
Guessing you got it stabbed out of time. Probably best to just start over by putting the motor at TDC, stab the dizzy and the rotor should point at the #1 cylinder post on the cap with the distributor fully installed. I install the cap and just make a mark on the adapter (what the cap connects to) where the #1 cylinder post is.

You have to be on the compression stroke or it will be 180 out.
Click to expand...
O god I did now I’m getting codes 91 31 41 I bought a pip sensor yesterday and the box looked messed up so I was already sus bout i. I stalled it so I literally going to swap it again in just a few
 

AeroCoupe

lube between the nut and the face. I know my lubes
Founding Member
Oct 28, 2001
5,814
3,950
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Claremore, OK
Apr 18, 2026
#26
  • Apr 18, 2026
  • #26
So 91 and 41 are O2's reading lean:
Code 41 is a RH side sensor, as viewed from the driver's seat
Code 91 is the LH side sensor, as viewed from the driver's seat

Do you still have the smog pump and crossover tube?
 
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Creomod

5 Year Member
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San Antonio,Texas
Apr 22, 2026
#27
  • Apr 22, 2026
  • #27
Guys I’m having issues I changed the distributor yesterday brand new lmk m,new fuel relay,fuel pump the ignition switch the fuel regulator car is sputtering not running right code 85,31 I don’t think the egr would cause this at all I have a extra one I’ll swap it in just a few minutes. Can it be a bad fuel injector? A leaking fuel injector . I’ve spent money already swapping out all the fuel components and now fuel injectors . Can a leaking injector cause this? How can I find a leaky injector ?
 

AeroCoupe

lube between the nut and the face. I know my lubes
Founding Member
Oct 28, 2001
5,814
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Claremore, OK
Apr 22, 2026
#28
  • Apr 22, 2026
  • #28
The codes are all over the place. Are you sure the ECU is good?

Only way I know to check a for a leaking injector is to read the plugs. If one of them is wet and smells like gas then there you go.
 

Creomod

5 Year Member
Sep 14, 2018
511
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San Antonio,Texas
Apr 22, 2026
#29
  • Apr 22, 2026
  • #29
AeroCoupe said:
The codes are all over the place. Are you sure the ECU is good?

Only way I know to check a for a leaking injector is to read the plugs. If one of them is wet and smells like gas then there you go.
Click to expand...
Damm I might have to have the ecu inspected Damm the plugs seem on they don’t reek of fuel damm the ecu I was thinking might be a problem
 

Noobz347

Stangnet Facilities Maint Tech... Er... Janitor
Admin Dude
Jan 4, 1985
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#30
  • Apr 22, 2026
  • #30
Double Damn!
 

Creomod

5 Year Member
Sep 14, 2018
511
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San Antonio,Texas
Apr 23, 2026
#31
  • Apr 23, 2026
  • #31
It almost feels like I’m in “limp mode” it’s not sputtering but feels like low fuel flow almost but I’m not sure anyone know what to look for in limp mode? Anyone know what causes this ?
 

nickyb

I gotta say i never painted my nuts, Never Ever
15 Year Member
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Apr 23, 2026
#32
  • Apr 23, 2026
  • #32
You replaced the distributor? Most new ones are absolute . My car ran like crap and stalled/shut off,I replaced three distributors from O'Reilly s.
Just maybe that's your problemo?
 
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Creomod

5 Year Member
Sep 14, 2018
511
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48
San Antonio,Texas
Apr 23, 2026
#33
  • Apr 23, 2026
  • #33
nickyb said:
You replaced the distributor? Most new ones are absolute . My car ran like crap and stalled/shut off,I replaced three distributors from O'Reilly s.
Just maybe that's your problemo?
Click to expand...
Bought it from lmr got the dynomod
 

nickyb

I gotta say i never painted my nuts, Never Ever
15 Year Member
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Apr 23, 2026
#34
  • Apr 23, 2026
  • #34
You would be better off with an old oem one.
 

Creomod

5 Year Member
Sep 14, 2018
511
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48
San Antonio,Texas
Apr 23, 2026
#35
  • Apr 23, 2026
  • #35
I honestly don’t think it’s the pump I might try that now I’m spending money on anything now
 

KRUISR

10 Year Member
Apr 16, 2015
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Apr 23, 2026
#36
  • Apr 23, 2026
  • #36
Creomod said:
Question I’m installing dustbutot and I don’t see the marks with the timming light and it sounds like a truck
Click to expand...
Take a piece of black board chalk and mark a line at "0" and "10" on the balancer. Then you can check your timing real easy.
 
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AeroCoupe

lube between the nut and the face. I know my lubes
Founding Member
Oct 28, 2001
5,814
3,950
183
Claremore, OK
Apr 24, 2026
#37
  • Apr 24, 2026
  • #37
I used a white paint pen on the Motorsport balancer in the T-Bird as those marks were very hard to read. The ones on the Fluidampr balancer in the Coupe were already white so very visible.
 
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Creomod

5 Year Member
Sep 14, 2018
511
42
48
San Antonio,Texas
Apr 25, 2026
#38
  • Apr 25, 2026
  • #38
AeroCoupe said:
So 91 and 41 are O2's reading lean:
Code 41 is a RH side sensor, as viewed from the driver's seat
Code 91 is the LH side sensor, as viewed from the driver's seat

Do you still have the smog pump and crossover tube?
Click to expand...
No I don’t I have them plugged.
 

AeroCoupe

lube between the nut and the face. I know my lubes
Founding Member
Oct 28, 2001
5,814
3,950
183
Claremore, OK
Apr 26, 2026
#39
  • Apr 26, 2026
  • #39
I read where the crossover tube would get plugged and would cause these codes so wanted to rule that out. If you can scrounge up a known good distributor you could try that but I am still leaning towards a bad ECU.
 
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KRUISR

10 Year Member
Apr 16, 2015
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Apr 26, 2026
#40
  • Apr 26, 2026
  • #40
Creomod said:
Now out of no where the car started . Fuel going to gauge.
Click to expand...
Mustang5L5 said:
Don't rule out corrected connections of brittle wiring as well here.
Click to expand...
I don't think anyone has said it yet, but a couple years ago I had similar fuel pump issues where it would just quit out of nowhere. I did the same fuel pump relay replacement, jumpered the pump on full time to test and everything would work. I would put the relay back in and all good for a while. Then out of the blue it would quit again.

For me, it turned out to be the connector in the driver side kick panel area. The power wire for the relay goes through this connector. What I found was the female pins had opened up and were not making good consistent contact with the male pin on the other side of the connector. A simple tap of your foot against the kick panel could cause the fuel pump to lose power - not a fault with the relay, just no power to the relay. To fix it I used a small precision screw driver to bend the two halves of the female pins inward and cleaned both sides of the connector. I haven't had an issue since.

I had to do the same thing with the pins on my power window switches as these were intermittent at times too. Worked great there as well.
 
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