97 expo not getting right fuel pressure

[strokin393]

I had someone put a gauge on my truck and its getting low fuel pressure, I think he said 30 at the most. What could that be, fuel pump, fpr, or injectors? The truck acts as it don't want to take gas when you hit throttle, it idles low then idles up every once in awhile and I think the fuel pressure jumps up as well. I'm thinking about changing the pump. I've changed the plugs and fuel filter already and checked the vacuum hoses already.

 

[strokin393]

Anyone? I'm thinking fuel pump or fuel pressure regulator but don't want to buy something and it not be it.

 

[Racenut]

I would start by replacing the fuel pressure regulator, there is a good chance that it will fix your problem and is cheaper than the pump ( about $60 ) from what I can find the cheapest pump is just over $200 up to almost $500 for a motorcraft .

 

[strokin393]

I found a fuel pump for around 60 but a fuel pump is much harder to change than a fpr. Can I test the fpr by taking the vacuum line off?

 

[Jackmldog]

I'm assuming you've tried replacing your fuel filter right? May want to do so if not already.

 

[strokin393]

I'm assuming you've tried replacing your fuel filter right? May want to do so if not already.

Fuel filter been changed, tb cleaned, vac hose checked and good, and mass air sensor cleaned. Its getting little fuel up there and won't stay running long or take gas when I hit the throttle.

 

[markanthony]

When U start the truck. Is their a small whine or whistle in the rear of the truck when standing on the outside of the truck. Is the whine whistle go away or changes sound when the engine rpm changes... If their is no whine or changes. I would hazard to say it is the pump.. Their should be a small whine to it when it is running. If the whine gets loud or is not their at all. The pump is not working.


The pump is lubed by the fuel. If the truck is ran out of fuel all lot the pump goes bad. My ford dealer told me the if the tank had a 1/4 tank or less. The pump is not in the fuel. It will be louder and not be lubed as good. So the pump wares out faster if the tank is most often with less then 1/4 tank of fuel.

Course. If is just one opinion of some guy at the dealer store.

 

[strokin393]

Yea, I didn't hear it so I went ahead and got a pump yesterday. I shall see when I put it in. Thanks

 

[Racenut]

The only time I can hear the pump on mine is when I first turn the key to the on position and do not start it. I can hear it build pressure then shut off.

It is a posibility that it is the pump and what you said about the 1/4 tank is correct. But one thing on a side note I have also seen pumps go bad but they still run so you hear it but it is pluged internaly so you get limited or no fuel to the injectors.

Hope the pump fixes the issue that is a big job.

 

[strokin393]

Thanks. I changed the pump earlier and just need to get some good clean gas to put back in the truck. I sure hope its fixed. Thank you all. I'll keep you posted. If not fixed, I'm changing the fpr.

 

[strokin393]

Still running the same. I don't know what else to do but change the fpr and maybe gut the converters.

 

[strokin393]

I'm thinking clogged cats, tps, or fpr. The truck starts runs, but not good at all, it idles real low, smokes white smoke, and try to give gas it wants to shut off or acts like its out of gas. I need ideas if any.

 

[strokin393]

I think its the cats, I unhooked them for a little and the truck runs and takes gas when you hit throttle. I didn't gie it much gas or let it run long, don't want to burn a valve. I need a mid pipe section with cats now.

 

[markanthony]

If you have the money.. I would just put in a new exhaust system. A cat back from flow master. Solves everything.

Or just clean them out and run them.

 

[strokin393]

I might have to beat the cones out. I don't have the money at the time to replace all at this time. It would be nice to get all new aftermarket exhaust for the truck. I just want to get it running right. Thanks

 

[Racenut]

You can cut out the rear cats and replace them with a piece of straight pipe. This will NOT cause a CEL, the bad thing is if you where to gut all of the cats you will loose quite a bit of low end power.

 

[Racenut]

Have you checked the fuel pressure again now that you put in the new pump?

If it is still around a max of 30psi then I would definatley change out the FPR before gutting the cats.

 

[strokin393]

Have you checked the fuel pressure again now that you put in the new pump?

If it is still around a max of 30psi then I would definatley change out the FPR before gutting the cats.

I don't want to bother the person that has the gauge, I might look into getting one, but the truck runs and takes gas when I hit throttle with the cats unhooked. I'd like to find another used exhaust to put on until i can come up with extra money to buy new.

 

[strokin393]

I tried to pull truck in the garage but doesn't want to move, won't or don't run to good with the y pipe halfway unhooked from the manifolds. It runs with it halfway hanging but not to good, can pull in the garage to take converters/cats off to have them gutted or replaced. I hope that's the problem tho, I don't want to spend to much money on stuff that I don't need.

 

[strokin393]

Ok took the y pipe off that has cats on it. Looked inside and saw the passenger side had gas or something wet I the pipe and saw that the cats on that side was gutted. I looked at driverside and it was dry and had the cone I the 1st cat don't know about other but sure that its in there. Now, why is that one side wet, anyone have any idea? I'm trying to get this truck running, we nbeed something to drive.