Fuel pressure regulator

Chasing a poor starting issue, fuel pressure drops really quick. I have a different regulator to try.
Any tips on removing the regulator?

what makes you think its the reg? they are notoriously reliable

I've never had to change one. Are they removable on a '96? I just went and looked at mine and it's part of the fuel rail. Mitchell says on a '96 it can be removed.

The outside canister of the FPR is part of the fuel rail, but there is a snap ring you can remove that allows you to remove the guts of the FPR.
I don't know off hand what is in there other than a spring, diaphragm and o-rings to seal it up.
I have never taken one apart either. As has been said they are notoriously reliable. But replaceable if necesary.

Like Rick said, It comes out with removal of the snap ring, not too hard. There is an O-ring or two in there. I replaced them when I replaced my injector O-rings, as the kit included rings for the fuel pressure reg.

Also could be a leaking injector.

Yeah, I saw the snap ring. I was asking about a '96. Repair procedure says to remove the 2 bolts and remove the FPR. Haven't ever payed attention to the '96 I spose.

Are we talking about SC or NA engine?

That prolly shoulda been our first question......

SC Riv, trouble started awhile ago. I have to give it gas to start. Replaced the fuel filter, oil does not smell like gas. Fuel pressure drops quickly after car is shut off. Figured I would try a different regulator before the fuel pump.

Well, the FPR is what holds the pressure when the car is shut off, not the pump. OR, you have an Injector that is leaking that bad. However, if an Injector is leaking that badly, you'd have a driveability concern along with a possible SES light.

Look to see if the FPR has a snap ring to remove. As stated before, my FPR is part of the fuel rail. For some reason Mitchell is telling me that on a '96 the FPR is held on by 2 bolts.

It has a snap ring, will probably try to change it this weekend.

Bleed pressure from system at shrader valve although it sounds like your system isn't holding much pressure anyway. lol I've replaced them before and it's pretty easy if you have the proper pliers to take the snap ring off. Harder to get it back into place. If the fuel pump is allowing leak-down, it will make the same condition (as far as I know). Fuel pump issues seem to be more prevalent than FPRs though.

There is a failrly easy way to check the FPR if you have the right tools. All you need is a vacuum pump with a gauge on it. Hook up the gauge to the vacuum port on the FPR and pump it up (about 5in/Hg). The vacuum should hold. If it bleeds away, or doesn't allow vacuum at all, your FPR is bad.

DEMonte1997 wrote:

Bleed pressure from system at shrader valve although it sounds like your system isn't holding much pressure anyway. lol I've replaced them before and it's pretty easy if you have the proper pliers to take the snap ring off. Harder to get it back into place. If the fuel pump is allowing leak-down, it will make the same condition (as far as I know). Fuel pump issues seem to be more prevalent than FPRs though.

I am hoping it is the regulator and not the pump.

You have to consider the fact that in order to have pressure after the key is off and pump is off, you need to have have both ends of the system tight.
One end, is the fuel pump with a check valve and the other end is the fuel injectors. Period.
Between those two is the FPR that can bleed fluid back to the tank, the fuel pump check valve that is leaking back into the tank and the fuel injectors that are leaking into the cylinders.
Need to check for all of those 3 possibilities to confirm why pressure drops after shut down.
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Just try turning the key to "ON" and not to start, and leave it in that position for a few seconds, when you want to start the car and see what happens.
If you are able to prime the fuel rail that way and start smooth, then you can possibly eliminate the fuel injectors as the possible culprit.

Without the special shut off valves that allow you to isolate the Injectors under pressure you will not know for sure. There are simple, yet expensive valves that will co into the quick disconnects on top of the supercharger, in the fuel rail, that allow you to measure the pressure at just the rail, which would include the FPR and injectors and then there are other pieces that allow you to further isolate the system.
I have used the GM tools made by OTC for that purpose before. But as Abaddon has said, I have yet to come across a bad FPR. Usually it is a bad check valve in the fuel pump if the pressure drops immediately, or a fuel injector if it drops slowly and causes a hard start situation.

I pivoted the front three injectors and sprayed all six with brake cleaner. The injector nearest the coil was a little sticky After doing this the car is starting ok now. When the temperature cools down in October I will pull the injectors and get them flowed and cleaned.

Any tips on the best way to pull the fuel rail, this car is so difficult to work on compared to my 87 Regal.

One thing to do that takes seconds is run the car and disconnect the vacuum hose to the FPR just to see if any gas comes out of the FPR vacuum port. That would tell you the internal diaphram is breached and it definitely needs to be replaced. Mind you it's still possible for the FPR to be bad if you don't have that symptom.
That said, I agree with the others on the regulator being reliable though. I've never heard of one going out on this motor before.

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Any tips on the best way to pull the fuel rail, this car is so difficult to work on compared to my 87 Regal.

Pulling the rail is fairly easy. Disconnect the battery. Depressurize the rail, then remove or reroute ignition wires. You need a special tool to disconnect the fuel lines at the rail. Move fuel lines out of the way. I don't think you need to loosen the alternator, but you may need to disconnect the wiring to it.

Disconnect the various electrical connectors and clips in order to move the rear wiring loom out of the way. Disconnect the connectors from the fuel injectors. There are 4 screws on the rail - remove them. The rail should come straight up with some light prying; the injectors may or may not stay attached the rail.