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stock regulator reads 90psi!!!!!?

  • Thread starter Thread starter torch93
  • Start date Start date Jan 15, 2012

torch93

Member
Aug 14, 2010
143
0
16
bakersfield c.a
Jan 15, 2012
#1
  • Jan 15, 2012
  • #1
hey guys been a while, i tried searching similar but not exactly mine situation and i'll try to make this short.
ok did wire tuck and had it for almost a yr
fuel pump relay and that other realy under the passenger wheel well by the strut.
washed it and totally forgot to cover em and washed full blast with the water hose
went to the movies and when i came out i cam smell fuel and coming from my car!
battery was dead and when i connected the cables i can hear a hissing from my bbk fpr and my fuel pump on when my key is off, ok thats why battery is dead, so went and bought new relays and unpluged the maf just so it can be driveable, ( pluged car didnt runs at all)
days later i pluged maf and relays back and still cutting out and black smoke.
i pulled off the vac on the fpr and FUEL pooring out !
took it off and apart and saw that fuel pump over pressurized the diaphragm causing it to stretch and rip.
i slapped on the stock 95 fpr (i have 95 fuelrails ) and car ran alot better but still not what it usually runs. i checked fuel pressure and it reads 98 and vac off 90 psi!!?? is stock regulator not strong enough for the 255 pump? is that why my car is not running its best?
again i tried searching but i just want to make sure i share all me symptoms .
im just so frustrated that im trying to narrow it down . thanks a million, you guys always come through.
 

FastDriver

I was uncomfortably high & wearing a helmet
SN Certified Technician
Sep 5, 2001
6,079
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Vass, NC
Jan 15, 2012
#2
  • Jan 15, 2012
  • #2
Honestly, I wonder if your fuel pressure gauge is accurate with a reading that high.... That's....HIIIIGHH. I don't think a normal 255LPH pump will push any fuel at that pressure.
 

ID89GT

10 Year Member
May 26, 2008
1,659
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49
Spokane Valley, WA
Jan 16, 2012
#3
  • Jan 16, 2012
  • #3
Also make sure your return line didnt get pinched
 

VibrantRedGT

"STANGNET'S PENGUIN SMACKER"
15 Year Member
Nov 29, 1999
14,679
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154
Boca Raton, Florida
Jan 16, 2012
#4
  • Jan 16, 2012
  • #4
That's like 3 times the normal psi it should run at. Obviously something is very wrong. The stock regulator can work with a 255LPH no problem although it's better to run an adjustable regulator to dial it in. Whatever happened there it killed your battery so it using electric. Might have to change that relay or drying it out, maybe the water is hurting the contact.
 

Noobz347

Stangnet Facilities Maint Tech... Er... Janitor
Admin Dude
Jan 4, 1985
43,015
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Box behind Walmart
Jan 16, 2012
#5
  • Jan 16, 2012
  • #5
ID89GT said:
Also make sure your return line didnt get pinched
Click to expand...

^ This ^ It sounds to me like something on the return side of your fuel system is blocked and/or BOTH of the regulators that you're in possession of, are bad.

Regardless of how long the fuel pump runs, your regulator should be returning all fuel above above the preset pressure, to the tank.

One way you can check is to disconnect the return line and route it to a gas can. If you still get high pressures then you know it's at the the regulator. If not, then some portion of the return system after the rail, is at fault.

Are you running an FMU by chance?
 

Rick 91GT

Mustang Master
Nov 29, 1999
9,692
95
99
PA
Jan 16, 2012
#6
  • Jan 16, 2012
  • #6
The car is NA, so no FMU.....

If fuel is coming out of vac line then, the reg diag is shot regardless....never seen anywhere near that pressure before, and everyone is right Id be taking a serious look at the return line.

J, I may have a stock and a Kirban reg at the shop you can try if needed, let me know.
 

Blown88GT

Founding Member
Nov 13, 1999
2,283
524
164
Palm Beach Gardens, FL
Jan 19, 2012
#7
  • Jan 19, 2012
  • #7
I'll bet a piece of the FPR diaphram is blocking the return line. See if the old diaphram is missing a piece. BTW, I had an FMU rubber fuel line swell internally & the pressure went to 100psi. The line finally split & I found out what was wrong after replacing the FPR & the problem returned.
 
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