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Fox dumping fuel at idle afr 10:1

  • Thread starter Thread starter Mattjhop23
  • Start date Start date Aug 5, 2024
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AeroCoupe

lube between the nut and the face. I know my lubes
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#21
  • Aug 14, 2024
  • #21
If you are going to stay with the stock block then I 100% agree with 2000xp8. The motor in my Coupe makes 460ish fwhp NA and I started looking for a better block as soon as I got the results from the engine dyno run. I can make more hp with a solid roller and pushing the rpm's but I am not wiling to grenade all the time and money I have in the motor.
 
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Mattjhop23

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#22
  • Aug 14, 2024
  • #22
TOOLOW91 said:
Start checking vaccum lines and make sure nothing is off. Causing the car to suck unmetered air will make it do odd things
Click to expand...
So I smoke tested and it was too, that was the first thing. So I checked the MAF harness plug I have 12v power I contacted pro-m and he told me to probe c&d and volts should move around “ I’m assuming with the car on to measure air” volts move to adjust air volume. So I back probed it and I got nothing I rev’d it a couple times and nothing stays at 0. I’m hoping he told me the correct wires if so I believe my MAF element is done. I’ll do it again just to be 100% and update again. Appreciate you all.
 

Noobz347

Stangnet Facilities Maint Tech... Er... Janitor
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#23
  • Aug 14, 2024
  • #23
2000xp8 said:
I don't think i'd waste time building out the fuel system for this engine.
IMO, just dial it back. 540rwhp is on borrowed time anyway not to mention the difference between 540rwhp and 500rwhp on the street is negligible.
I think people underestimate how long and how much money replacing an engine that split the block costs.
Blowing it up in epic fashion could be a 20k mistake that takes years to correct (if ever).
Click to expand...

Agreed... How long does the burnout stripe need to be? LoL
 

Mattjhop23

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#24
  • Sep 2, 2024
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Welp I haven’t touched the car all that much. Kinda just been blah with the car since it’s been down for the big yearly shows I was trying to attend. Welp I’ll check vacuum lines today and fpr like someone mentioned I did get MAF checked out was good and put new wires and distributor in. Rotor and pickup was corroded but nothing same ole same ole. A tuner told me my sct chip could have went bad he’s seen it happen a few times. I think ima pull the O2’s and check what you all suggested. Sorry for the month wait just haven’t been motivated to mess with the car. I’ve burned through 2 sets of plugs idling the car for 10-15 minutes total. Plugs aren’t getting any cheaper that goes for anything nowadays. Have a good holiday weekend appreciate you all
 

Mattjhop23

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#25
  • Sep 2, 2024
  • #25
TOOLOW91 said:
Start checking vaccum lines and make sure nothing is off. Causing the car to suck unmetered air will make it do odd things
Click to expand...
So I pulled vacuum line from fpr it’s fed to the side of the upper intake, well I pulled it and fuel is dripping out of it. So. Fpr is leaking?
 

89ripper

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#26
  • Sep 2, 2024
  • #26
Mattjhop23 said:
So I pulled vacuum line from fpr it’s fed to the side of the upper intake, well I pulled it and fuel is dripping out of it. So. Fpr is leaking?
Click to expand...
Sounds like the diaphragm is, yes.
 

Mattjhop23

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#27
  • Sep 2, 2024
  • #27
89ripper said:
Sounds like the diaphragm is, yes.
Click to expand...
Welp I pulled the upper completely filled with gas. Should I pull the lower intake and check it out? Really don’t “want” to seeing I just redid the lower intake beginning of summer
 

89ripper

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#28
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Mattjhop23 said:
Welp I pulled the upper completely filled with gas. Should I pull the lower intake and check it out? Really don’t “want” to seeing I just redid the lower intake beginning of summer
Click to expand...
What fpr are you running? I would start there. The diaphragms go bad and suck gas through vacuum line
 

Mattjhop23

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#29
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It’s a aeromotive that was on the car when I got it. I’m going to swap it out I pulled upper intake was filled with gas so I don’t want to but I guess I should pull the lower intake to?
 

General karthief

wonder how much it would cost to ship you a pair
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#30
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  • #30
Shouldn't have to pull the lower, no place to puddle.
 
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AeroCoupe

lube between the nut and the face. I know my lubes
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#31
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You can get a rebuild kit for the Aeromotive FPR, just saying.
 

89ripper

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#32
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Yes i have had to rebuild aeromotive fpr before its fairly simple to do
 

TOOLOW91

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#33
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Rebuild fpr , put it back together and set fuel pressure . Run it it’ll burn all that excess out in a few mins

If you’re nervous about cylinders full of fuel pull plugs and crank motor a few turns. Also and a big one !!!! Do not run the engine another second without changing oil. I’m sure it’s beyond washed
 
Reactions: 89ripper, Cheapskate207 and AeroCoupe

Mattjhop23

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Apr 21, 2024
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Sep 3, 2024
#34
  • Sep 3, 2024
  • #34
TOOLOW91 said:
Rebuild fpr , put it back together and set fuel pressure . Run it it’ll burn all that excess out in a few mins

If you’re nervous about cylinders full of fuel pull plugs and crank motor a few turns. Also and a big one !!!! Do not run the engine another second without changing oil. I’m sure it’s beyond washed
Click to expand...
Yea I have some rotella in swapping oil today. This fpr has seen better days. It plums into fuel rails “stock rails” I know rails are maxed injectors are maxed fuel system upgrade this winter. But around by the o-ring is banged up missed a screw in the bottom other one is stripped. I’m just going to order a new one and have no worries about it. I’m sure cylinders will be washed down by the time the new one gets here and installed. Only thing is my v2 pulls oil from the pan and runs it through it so supercharger is been pulling gas soaked oil .
 
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