fuel pressure regulator
#1
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Car: 86 IROC
Engine: 5.0 TPI
Transmission: 700-R-4
Axle/Gears: 2.73 open
fuel pressure regulator
i need to replace the fuel pressure regulator on my TPI car . but i dont want to fool with the cheap *** diaphram that seems to be all we can get . i want the WHOLE thing . who uses what ? and where can i get one . summit only offers diaphrams and FPR covers
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Car: 1987 Trans Am
Engine: 355 Edel Int, SLP, Edel heders 8PSI
Transmission: T5
Axle/Gears: 3.45 Borg Warner
Re: fuel pressure regulator
i just did the BBK adjustable housing and the Echlin(napa) diaphragm. $50 + $90. works great!
#4
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Car: 1987 Trans Am
Engine: 355 Edel Int, SLP, Edel heders 8PSI
Transmission: T5
Axle/Gears: 3.45 Borg Warner
Re: fuel pressure regulator
well than i suggest hopping in a deloreon and driving 88 mph to 1985
#5
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Car: 87 IROC
Engine: L31 350
Transmission: T56
Axle/Gears: 4.10 D44
Re: fuel pressure regulator
@Rusty - The only other part is the base block of aluminum that is part of the fuel rail assembly. That + diaphragm + cover = FPR. You can re-use the stock cover, or get an adjustable one. That leaves finding a quality replacement diaphragm. Don't forget the special anti-tamper T8? torx driver that is needed, and does come with most (all?) AFPR covers.
Or, watch the classifieds to get a used fuel rail assembly.
Or, modify the stock rails to use an external, aftermarket AFPR.
Or, get aftermarket fuel rails + aftermarket AFPR.
Or, watch the classifieds to get a used fuel rail assembly.
Or, modify the stock rails to use an external, aftermarket AFPR.
Or, get aftermarket fuel rails + aftermarket AFPR.
#6
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Car: 86 IROC
Engine: 5.0 TPI
Transmission: 700-R-4
Axle/Gears: 2.73 open
Re: fuel pressure regulator
actually , have you heard that brand new de lorians are being built as i type this . AND the projected cost is less than $100,000. something like that with a turbo LS3. hmmmmmm
#7
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Car: 1938 Chevy 2 dr Sedan
Engine: Dart400 AFR190 TPIS ZZ409 Big Mouth
Transmission: Gearstar 700R4 level 4
Axle/Gears: Moser 12bolt-Det Trac loc 3:42
Re: fuel pressure regulator
Street and Performance, located in Mena, Az. has an OEM unit complete in their on line catalog. Nice folks to deal with I might add.
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#8
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Car: 87 IROC
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Re: fuel pressure regulator
Google found this catalog page, producing part # 17112281 for $156/166/176 for natural/polished/chrome. It is discontinued anywhere else. Considering a new diaphragm is $70-$80, the asking price, if still available, isn't bad.
#9
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Car: 1938 Chevy 2 dr Sedan
Engine: Dart400 AFR190 TPIS ZZ409 Big Mouth
Transmission: Gearstar 700R4 level 4
Axle/Gears: Moser 12bolt-Det Trac loc 3:42
Re: fuel pressure regulator
S&P is an Mena, AR... Arkansas not Arizona.
Google found this catalog page, producing part # 17112281 for $156/166/176 for natural/polished/chrome. It is discontinued anywhere else. Considering a new diaphragm is $70-$80, the asking price, if still available, isn't bad.
Google found this catalog page, producing part # 17112281 for $156/166/176 for natural/polished/chrome. It is discontinued anywhere else. Considering a new diaphragm is $70-$80, the asking price, if still available, isn't bad.
#10
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Car: 86 IROC
Engine: 5.0 TPI
Transmission: 700-R-4
Axle/Gears: 2.73 open
Re: fuel pressure regulator
so , if a FPR will hold vaccuum . is it a safe bet it isnt leaking ?? and i think the extra fuel is coming from my cold start injector. anyone know if south bay has them ??
#12
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Car: 1988 GTA Trans AM
Engine: 305
Transmission: 5 speed
Re: fuel pressure regulator
I replaced my FPR as it was leaking into the plenum, I replaced with a brand new ac delco, no more leaks however car does not hold fuel pressure, (and runs like poop) after turned off, drops instantly to 0, I followed instructions and pinched the fuel lines to determine if it was a check valve or pump issue
what is a good brand to purchase for a FPR, or if someone has one and willing to ship to Canada please let me know, would like one with adjustable pressure, but as long as it works that is fine
what is a good brand to purchase for a FPR, or if someone has one and willing to ship to Canada please let me know, would like one with adjustable pressure, but as long as it works that is fine
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Car: 1938 Chevy 2 dr Sedan
Engine: Dart400 AFR190 TPIS ZZ409 Big Mouth
Transmission: Gearstar 700R4 level 4
Axle/Gears: Moser 12bolt-Det Trac loc 3:42
Re: fuel pressure regulator
I replaced my FPR as it was leaking into the plenum, I replaced with a brand new ac delco, no more leaks however car does not hold fuel pressure, (and runs like poop) after turned off, drops instantly to 0, I followed instructions and pinched the fuel lines to determine if it was a check valve or pump issue
what is a good brand to purchase for a FPR, or if someone has one and willing to ship to Canada please let me know, would like one with adjustable pressure, but as long as it works that is fine
what is a good brand to purchase for a FPR, or if someone has one and willing to ship to Canada please let me know, would like one with adjustable pressure, but as long as it works that is fine
#16
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Car: 1988 Trans Am GTA
Engine: 350 TPI (L98)
Transmission: TH700R4
Axle/Gears: 3.27 9-bolt w/ Torsen LSD
Re: fuel pressure regulator
I had the same problem. Disassemble the unit and inspeçt the flow control valve, flat disc, and the SS seat in the fuel well. The diaphragm disc has to be mirror like smooth no machined marks if it not absolutely smooth fuel under pressure escapes past disc and the stainless steel port back in the fuel rail.
(Side note: I'm very satisfied with the Bosch III TPI injectors I bought from you though.)
edit:
Have you checked that you put the big vacuum hose for the brake booster back on the plenum? Easy to forget, and the car runs like **** when it's off. I missed that, and only caught it because I replaced the plugs&wires after the FPR. I didn't hear a hiss or anything.
Last edited by keykey; 02-16-2016 at 11:13 AM. Reason: vacuum hose
#17
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Re: fuel pressure regulator
I wish you would have contacted us. We want you to be happy. We sell the regulators and the diaphragms every day. What marks are you referring to? The diaphragm is the stock GM.
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Car: 87 Iroc 5.7,67 SS Camaro,90 Formula
Engine: 355 AFR Superram LPE 219
Transmission: 700r4 3000 stall 4spd 5 spd
Axle/Gears: 3.27
Re: fuel pressure regulator
south bay fuel injectors has it they are a sponsored vendor here
#19
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Car: 1988 Trans Am GTA
Engine: 350 TPI (L98)
Transmission: TH700R4
Axle/Gears: 3.27 9-bolt w/ Torsen LSD
Re: fuel pressure regulator
This image is from a parts vendor page, the marks are pretty rough and looks just like them but "round" instead of straight, and they could be felt with your fingernail.
On the old stock regulator which was removed because of a torn rubber diaphragm, the button/disc had a mirror blank finish, and if you drag your fingernail on it, it feels like a glass mirror (perfectly smooth).
Before I put it in the second time when I had a little bit of a panic because the diaphragm broke in my dad's parking lot 190 miles from home and no choice but to use this regulator, I "wet polished" it a bit myself with very fine emery cloth to get it at least a little bit more flat.
The car runs ok now, but the pressure still drops immediatly (to zero in about 3-4 seconds) when the pump shuts off, and I have a feeling it's a little down on power, and the crank is longer than with the stock regulator before it starts because the pressure takes longer to build.
With the old regulator, pressure held perfectly at 50 psi for at least 10 minutes, and the cranking time for engine start was next to nothing.
#20
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Re: fuel pressure regulator
did you purchase the regulator and diaphragm from us? Why don't you return whatever you purchased from us.
Want to see what the deal is.
Want to see what the deal is.
#21
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Car: 1988 Trans Am GTA
Engine: 350 TPI (L98)
Transmission: TH700R4
Axle/Gears: 3.27 9-bolt w/ Torsen LSD
Re: fuel pressure regulator
I'll get photos of the stuff while it's apart anyway. If I can't get pressure to hold even when I've tried swapped the discs, I'll probably buy a new diaphragm again. Then I could send the old one back to you so you can have a look at it.
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Car: 1988 Trans Am GTA
Engine: 350 TPI (L98)
Transmission: TH700R4
Axle/Gears: 3.27 9-bolt w/ Torsen LSD
Re: fuel pressure regulator
Just got home after a few hours in the garage! I brought a real camera too, and got some really good photos!
My theory proved right, there is definitely something wrong with the regulator i got from you, you can see it very clearly in the photos that it doesn't seal. I took photos of it side by side with the old one so you can compare.
Mirror blank disc to the left, bad disc to the right.
Literally mirror blank, you can see the camera lens reflection on the disc.
Bad disc with marks on it, and now that it's been in the engine for some miles you can see that it doesn't seal all the way around.
I managed to do a half-assed swap of the discs and put the regulator from south bay back in the car with the old disc. It holds a very small pressure now, but not as much as with the old regulator. Unfortunately I cannot start the car right now to try the cranking time, but I will report back further when the snow is gone here.
If you want to send me another diaphragm as Goodwill, it would be much appreciated. Since i work as a mechanic, I don't trust the half-assed repair I did so I need a new regulator to keep in the car regardless if this works, so that I'm prepared for a roadside repair.
If you think you can send me another one, it would be cool if you could take a quick look at it before shipping so that one is okay.
My theory proved right, there is definitely something wrong with the regulator i got from you, you can see it very clearly in the photos that it doesn't seal. I took photos of it side by side with the old one so you can compare.
Mirror blank disc to the left, bad disc to the right.
Literally mirror blank, you can see the camera lens reflection on the disc.
Bad disc with marks on it, and now that it's been in the engine for some miles you can see that it doesn't seal all the way around.
I managed to do a half-assed swap of the discs and put the regulator from south bay back in the car with the old disc. It holds a very small pressure now, but not as much as with the old regulator. Unfortunately I cannot start the car right now to try the cranking time, but I will report back further when the snow is gone here.
If you want to send me another diaphragm as Goodwill, it would be much appreciated. Since i work as a mechanic, I don't trust the half-assed repair I did so I need a new regulator to keep in the car regardless if this works, so that I'm prepared for a roadside repair.
If you think you can send me another one, it would be cool if you could take a quick look at it before shipping so that one is okay.
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Car: 1988 GTA Trans AM
Engine: 305
Transmission: 5 speed
Re: fuel pressure regulator
So I finally got around to installing a new adjustable FPR from southbay
great quality product, only prob is they are a PITA to adjust once the plenum is installed
The car runs much better however once turned off the pressure drops to 0 still, it does drop much slower, but is at 0 within 20 seconds of shutting off car, last FPR it was instantly at 0
great quality product, only prob is they are a PITA to adjust once the plenum is installed
The car runs much better however once turned off the pressure drops to 0 still, it does drop much slower, but is at 0 within 20 seconds of shutting off car, last FPR it was instantly at 0
#27
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Car: 1988 Pontiac Firebird Formula
Engine: 5.7 TPI
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Re: fuel pressure regulator
Pinch off the return line, and see if pressure still bleeds off just as quickly. If it does, it's the check valve in the pump, not the regulator.
#28
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Car: 1988 GTA Trans AM
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Transmission: 5 speed
Re: fuel pressure regulator
What should pressure be at while running?
I set it to bout 45 with hose off regulator and then connect vacuum and it runs at bout 40 is that correct how it dropped?
#30
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Re: fuel pressure regulator
another bad regulator WTF?
the adjustable one I got from southbay looks just like the one described in this thread, its all scratched up, not smooth, do I have the same problem?
the adjustable one I got from southbay looks just like the one described in this thread, its all scratched up, not smooth, do I have the same problem?
#31
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Re: fuel pressure regulator
What regulator is scratched up????? Are you referring to the diaphragm. We get them directly from GM! I can show you a pic of everyone that we get. They are not shiny
#32
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Car: 1988 GTA Trans AM
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Re: fuel pressure regulator
yes the diaphram is scratched just like keykey's
I am just looking for direction, is it the regulator or pump, is there a way I can tell, other than what has been suggested?
I am just looking for direction, is it the regulator or pump, is there a way I can tell, other than what has been suggested?
#33
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Car: 1988 Trans Am GTA
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Transmission: TH700R4
Axle/Gears: 3.27 9-bolt w/ Torsen LSD
Re: fuel pressure regulator
It doesn't matter if there are tiny "scratches", they just can't be rough to the feel. South Bay sent me a new one, and it wasn't mirror blank, it looked "scratched" too, but it works like it should. So just because it's not blank doesn't mean it's faulty.
If you don't have a longer cranking time than normal it doesn't really matter that the pressure drops slightly when the pump shuts off.
The problem with my old one was some kind of machining fault that made it not seal att all which led to longer cranking time and lower fuel pressure when pump was operating.
If you don't have a longer cranking time than normal it doesn't really matter that the pressure drops slightly when the pump shuts off.
The problem with my old one was some kind of machining fault that made it not seal att all which led to longer cranking time and lower fuel pressure when pump was operating.
#34
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Car: 1988 GTA Trans AM
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Re: fuel pressure regulator
OK, but why do people say that if you pinch the return line and pressure holds then it is a defective FPR and not the check valve?
#35
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Car: 87 IROC
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Re: fuel pressure regulator
If the pressure drops, then either the check valve must have failed (fuel back flows the feed line), OR one or more injectors leaked out the fuel. So, you cannot tell if the FPR is ALSO leaking.
Therefore, if the pressure HOLDS, ...
... the check valve on the fuel pump side prevents back flow down the feed line.
... none of the injectors leaked.
... and the pinched return line holds pressure on the return side.
Therefore, when you un-pinch the return line, and the fuel pressure drops, it must be the FPR that "leaked" the pressure.
#38
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Re: fuel pressure regulator
Update
fuel pressure still drops like a rock when key off -- oh well i guess
ended up taking car to local shop that actually knows how to work on a TPI, long story short, 2 new MAF relays and a new, expensive MAF, not purchased from Rock Auto and wow the car runs amazing
fuel pressure still drops like a rock when key off -- oh well i guess
ended up taking car to local shop that actually knows how to work on a TPI, long story short, 2 new MAF relays and a new, expensive MAF, not purchased from Rock Auto and wow the car runs amazing
#39
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Car: 1988 Trans Am GTA
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Re: fuel pressure regulator
Good news . As I've understood it, it doesn't really matter if pressure drops when key turned off, as long as you have SOME pressure holding for starting, and full pressure as long as the pump is running. My car runs great now, and the pressure doesn't hold like it did with the factory regulator.
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