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Fuel Pressure Regulator?

Today, my 1995 E150 suddenly started acting like it was running out of fuel Lucky for me, this happened close to both a parts store and my usual mechanic’s shop. Unluckily for me, it happened on Saturday, and my shop can’t get to it until Thursday. So here I am, hoping to do a fix in the meantime.

At first, it seemed that it must have been the fuel pump, because I couldn’t hear it come on when I turned on the ignition. Then, a guy who said he was a mechanic told me he could hear the pump cycling, and that my problem was the fuel pressure regulator. So he managed to start the vehicle after a few tries, then it crapped out again. He did this twice. Then he went away.

I called every parts store in town, and none of them had a fuel pressure regulator for my vehicle, and the earliest any of them could get one was Monday. But I knew I was due for a fuel filter, and I’d changed filters on this vehicle before, so I got one of those and put it in. To my delight, the van started right up and idled beautifully. In fact, it ran beautifully for about 15 minutes, until I came to a slight rise, then it crapped out again. It still started up and idled smoothly, and even revved up smoothly, until it reached a high idle speed, at which point it crapped out. I did manage to limp into the parking lot of my shop - which, again, can’t get to it until Thursday.

So my question is: does this sound like a fuel pressure regulator to you? If so, is that a job which somebody with a reasonable mechanical aptitude (i.e., at least good enough to change the fuel filter) should be able to feel safe doing? If the answer to those two is “yes” (or even if it’s “no”), any other helpful suggestions?

Thanks in advance! :slight_smile:

It sounds more like a fuel pump to me.

I thought so too, until it started up and idled smoothly. I’ve had a fuel pump failure in this vehicle before, and when it failed it didn’t start at all until the new pump was installed


I probably should have mentioned that the tank was close to empty, but not quite, and that I’d added about 3 gallons to it before changing the filter.

I was also able to start the thing on a hill, with the engine elevated above the tank. It just didn’t want to move up the hill. I also tried backing it uphill, and it seems to behave exactly the same as going forward uphill - which I remember the guys talking about in an old show.

It could be. You may want to measure the fuel pressure before you replace the fuel pressure regulator, though.
Your van also has two fuel pumps, I believe. It could be that one is having issues.

Just last week a tradesman was stalled out in front of my door so lent him a hand to get going. It was the exact same van (but a 2001) with a similar problem. After some probing, his issue was with this “inertia fuel shut off switch”, located behind a panel by the passenger’s right foot. It is supposed to cut the fuel pump’s power in case of a crash. It has a button that allows one to reset the condition but his device looked intermittent so we shorted the thing out and he was on his way.

Just saying: it could be a couple of things. Don’t throw parts at it because that can get expensive.

The model year of your truck is also one of the last years to use the TFI ignition module. These are prone to heat related failures and the symptoms can vary but generally it’s similar to running out of gas or stalling dead. Once dead it may restart or it may have to sit a while before restarting at which point it may run fine for varying amounts of time.

What engine is in this truck?

The engine is the 5L V8.

And I did try the inertia fuel shutoff switch. It was in a hard place to find, and I didn’t have the owner’s manual, but another mechanic guy who’d stopped to help found it for me. If it hadn’t been for him, I might still be looking for it.

That inertia switch can be intermittent, like with the guy that got stuck in front of my door. I pulled the connector out and put a piece of wire across the two contacts in the connector.

If that doesn’t help, you may want to check your fuel pressure before you actually start replacing things.

I’m guessing you check the pressure by putting a gauge somewhere on the fuel line? I’m also guessing it should have the same kind of connectors as the fuel filter and other parts in the fuel line?

Is this a tool that most parts stores would have on the shelf?

Yup. There’s often a service port that you screw this tool into. Not sure where that is on an e150, though.
Basically you want to make sure your pressure is okay before committing to anything.
I know harbor freight sells one. Not sure if places like Autozone or Pepboys have one.

Edit: Sears sells one as well, I see now.

I live in Maine. Which isn’t the end of the line, but you can almost see it from here.

We do have an autozone here, but the nearest Harbor freight I know of is in Pennsylvania. And the only reason I know that one is because I broke down near it. :wink:

You can do a preliminary check of the fuel pressure regulator. Start the engine and let it idle for a minute and shut the engine off. On the fuel rail remove the vacuum hose from the pressure regulator. If gas leaks out of this connection the regulator is leaking and requires replacement.

Here’s what the fuel pressure regulator looks like.


Lol. Well, there are two within 15 minutes of my house and I’m on your way to PA in CT. While you’re here, I can probably check it for you. :slight_smile:

Try autozone or perhaps sears. They sell actron tools, I think. Perhaps first investigate how one measures the pressure for that van of yours. GM uses a different port, I think - not all tools accommodate it.
Perhaps Autozone can even lend you theirs. If I’m not mistaken, they rent out tools.

Edit: I like tester’s suggestion.

I like Tester’s suggestion too, especially since it doesn’t involve buying anything. :slight_smile: My only question right now is where’s the fuel rail? I do have a Chilton’s manual (in the vehicle), but it’s usually not very good at telling you where a part is.

I’m currently about 15 miles from the vehicle, and on foot until I can wangle a ride. So there’s not much I can do for a test until then - maybe sometime tomorrow or Monday. The shop manager did say that they wouldn’t object to me working on the vehicle there. I guess they want me to think of them when it comes time for a job I can’t do. :wink:

This library site has a lot of service information for lots of modern cars:
To get in, enter barcode 02378001078755

That’s where I found that info for the guy stranded in front of my door last week. You can also very often find free pdf factory manuals for cars and trucks by googling around. Russia seems to be a good source of stuff.

A quick look shows the 5.8 does use the TFI module so keep that in mind if all else fails. A faulty module can also cause the fuel pump to be inoperative.

If the engine loses fuel pressure and stalls due to a failing pressure regulator pinching the return line will raise the pressure and the engine should start. Be aware that if the pump is working and the regulator is the problem pinching that line will dead head the pump and the pressure might exceed 100 psi and extended operation at that pressure will cause the pump to fail or a line to burst. Ford regulators are notorious for failing so that fuel leaks to the vacuum line but they rarely fail causing pressure to drop to the point that the engine stalls. But they do on rare occasion.