5.0 Fuel press regulator

[stangman16]

How hard is it to change out the Fuel Pressure regulator on a stock 5.0 89-93 Mustang? Do I need to take off the fuel rails in order to do so?

I went through the EFI no-start checklist, and fuel does not come out through the opening of the vacuum port on the regulator when 'on' and even while cranking - so I'm guessing it's shot (looks old anyhow & the pump is working).

Are there any special tools required to remove it?

Thank you!

 

[68EFIvert]

I just changed mine. There are three allen bolts that you can access from the bottom of the fuel rail. Take those out and drop in the new one. Really easy. Do you have a fuel pressure guage? If not you may want to get your hands on one. I think Jeg's sells them for $35. If you need a new regulator I have one the I replaced for an adjustable one you can have for the cost of shipping.

Darreld

 

[91ghp5.0]

It really helps if you take off the upper intake. I tried to do it without taking off the upper plenum, and I couldn't get the last bolt. That's on the to do list! Other than that...it's pretty darn simple.

 

[ozanracing]

fuel does not come out through the opening of the vacuum port on the regulator

That's good. It's not supposed to,. It is, afterall, a vacuum fitting.

 

[stangman16]

That's good. It's not supposed to,. It is, afterall, a vacuum fitting.

Posted by: jrichker

"F.) Fuel pressure regulator failed. Remove vacuum line from regulator and inspect
for fuel escaping while pump is running."

I guess I mis-understood this, so since fuel is not escaping then my regulator is just fine?

 

[88-5.0mustang]

yeah it should be just fine.. its shot if their is fuel comming out of the port.. i think that means the diaphram is pooched..

 

[stangman16]

goodness... leave it to me to get that backwards. Thank you guys for saving me some money and the headache of changing it out.

back to more diagnosis on the no start (with fuel & spark) condition.

 

[88-5.0mustang]

i would still get a fuel pressure gauge on it just so u know what kinda pressure u have going threw the rails

 

[stangman16]

Is there one that would work with the stock fuel rail and pressure regulator that you can recommend?

 

[91ghp5.0]

You can put one on the fuel rail I believe...there is a port on it, if I'm not mistaken. The aftermarket fuel pressure regulator has a port on itself for a gauge. If you have the cash, it's a great supporting mod for later things (HCI/blower/nitrous/turbo).

 

[Strype]

Is there one that would work with the stock fuel rail and pressure regulator that you can recommend?

You can put one on the fuel rail I believe...there is a port on it, if I'm not mistaken. The aftermarket fuel pressure regulator has a port on itself for a gauge. If you have the cash, it's a great supporting mod for later things (HCI/blower/nitrous/turbo).

NOS makes an adapter for FPRs- that's what I used. Put plumber's tape around it. (teflon)

Oh yeah, you'll have to take out the shraeder valve fitting. There's a tool for that.

 

[Lxpony]

It is much easier with the upper manifold off

 

[91ghp5.0]

It is much easier with the upper manifold off

Agreed. I still haven't gotten that damn third (farthest away) screw on. I tried to do it without taking off the manifold. Oh well. Maybe this weekend when I'm installing the gauges

 

[Lxpony]

I got that one out my cutting down the size of my Allen wrench with my Dremel so there was clearance. It would have been easier with the fuel rail off.

 

[jrichker]

The auto parts stores have gotten better about renting/loaning test tools. I recommend that you check and see if there is a fuel pressure test gauge available for loan/rent. I spent $35 and bought one because it looked like a good tool to own.

The cheap & dirty way is to use a tire pressure gauge, but the acccuracy may be a bit off. Watch out for the squirting fuel if you try the tire gauge...

 

[JChalfan]

I got that one out my cutting down the size of my Allen wrench with my Dremel so there was clearance. It would have been easier with the fuel rail off.

That's what I've done in the past too, worked great. It was really the only way to do it with the manifold still on.

Jeff

 

[rickd93_lx]

The auto parts stores have gotten better about renting/loaning test tools. I recommend that you check and see if there is a fuel pressure test gauge available for loan/rent. I spent $35 and bought one because it looked like a good tool to own.

j, would dropping a fuel pressure guage offset the calibration of the guage? the reason i ask is most parts stores(franchise) have a bunch of kids who really dont care about there jobs throwing tools around, i was going to rent a torque wrench from a. zone and the guy dropped it from about 4.5 feet up, picked it up handed it to me and said dont worry there tough. i dont trust auto parts stores tools that require precise measurements. just my 2, but if droping a guage does not do the same as dropping a torque wrench themn it would be fine i guess.