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NEED HELP! p1237 fuel pump secondary circuit fault

  • Thread starter Thread starter Project_2v_
  • Start date Start date Mar 28, 2023
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    #newedge mustang mustanggt sn95

Project_2v_

New Member
Oct 18, 2021
4
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1
California
Mar 28, 2023
#1
  • Mar 28, 2023
  • #1
Hey guys I have a a 2002 mustang gt. it’s FBO WITH TRICKFLOW STAGE 2 CAMS. Dyno tuned. I’m running into some fuel problems I guess and with that code I also have a random misfire which is P0300. I’m hoping to see if the p1237 code is the reason why I’m misfiring. Already did spark plugs with ngk iridium’s, new fuel pump/filter, fuel pump regulator maybe I’m missing a ground? I haven’t checked fuel injectors yet…If any of you guys have any input let me hear it, cus I’m been wrestling with this for like two months and working on it everyday haven’t seem to find the issue yet or if anyone has had experience with this I’m probly forgot some things I’m sure it’ll get asked

Also here’s a clip of the fuel pressure it dances around between 40 then drops down to 10 then will go above 80 sometimes then will shut off
 

Project_2v_

New Member
Oct 18, 2021
4
0
1
California
Mar 28, 2023
#2
  • Mar 28, 2023
  • #2
Here is the fuel pressure reading
 

Project_2v_

New Member
Oct 18, 2021
4
0
1
California
Mar 28, 2023
#3
  • Mar 28, 2023
  • #3
Project_2v_ said:
Hey guys I have a a 2002 mustang gt. it’s FBO WITH TRICKFLOW STAGE 2 CAMS. Dyno tuned. I’m running into some fuel problems I guess and with that code I also have a random misfire which is P0300. I’m hoping to see if the p1237 code is the reason why I’m misfiring. Already did spark plugs with ngk iridium’s, new fuel pump/filter, fuel pump regulator maybe I’m missing a ground? I haven’t checked fuel injectors yet…If any of you guys have any input let me hear it, cus I’m been wrestling with this for like two months and working on it everyday haven’t seem to find the issue yet or if anyone has had experience with this I’m probly forgot some things I’m sure it’ll get asked

Also here’s a clip of the fuel pressure it dances around between 40 then drops down to 10 then will go above 80 sometimes then will shut off
Click to expand...
Let me know if the video uploaded for you guys!
 
Z

ZorrySteel

New Member
Jun 7, 2024
2
0
1
Texas
Jun 7, 2024
#4
  • Jun 7, 2024
  • #4
Project_2v_ said:
Let me know if the video uploaded for you guys!
Click to expand...
hi!!! You fix your problem?
 
Z

ZorrySteel

New Member
Jun 7, 2024
2
0
1
Texas
Jun 7, 2024
#5
  • Jun 7, 2024
  • #5
Project_2v_ said:
Let me know if the video uploaded for you guys!
Click to expand...
Video? Show me the video please
 
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