Fuel Pressure Regulator

What is the purpose of the fuel pressure regulator? Where is the fuel pressure regulator located and how hard is it to change.. Thank U

What is the purpose of the fuel pressure regulator? Where is the fuel pressure regulator located and how hard is it to change.. Thank U

Not to sound obvious but i assume it keeps the fuel pressure from becoming too great. It's located on the fuel rail on the driver's side. Chiltons says you need to remove the upper intake (the top part that says 3100 SFI...) but it looks like it would be easy to change without taking this off. Anyone know if the manifold does indeed have to be removed?

One test I have read about is that you can remove the vacuum line, and if you smell gas, the regulator is indeed bad.

What eng and trans and what year and mileage?
Just what it says it regulates the fuel pressure.
Why do you want to change it?
Have you checked your fuel pressure for up to specs?
MT-2500

The reason i'm asking (MT-2500) is because i am losing alot of gas, i filled the car up on saturday night drove around a little, on sunday i didn't drive at all, monday drove the car some and today i have a half tank of gas. Please help because putting gas in the car is killing me :-(

If it is starting and running good it is not fuel pressure reg.
Check tune up end.
Watch for fuel leaks someplace.
Have you got a locking gas cap or large shotgun or big dog?
Mt

I have a lock gas cap. I looked for leaks didn't find or see any. The car has power that's why i don't understand why i'm losing alot of gas.

What eng and year and mileage?
hat is your gas mileage? In town and on highway?
Sometimes the gas gauge will drop from full to 1/2 real fast. Fill it back up and see if it realy takes a half tank to fill it up.
Start checking your gas mileage real close.
After it has been parked overnight see if the gas gauge is the same as you parked as check the mileage on the odemeter.
Post back your gas mileage.
MT

3.1 V6 and i have 146223 miles and as far as the mileage i'm not really sure but i think is something like 17 mpg. Thank you for the help. One more thing MT-2500, when i'm on a hill going up the gas gauge move down (about 3 lines) like i'm losing gas and when i'm going down the hill the gas gauge moves up (about 2 lines) making it seem like i have more gas than i do. Then when i get back on level ground the gas gauge goes back to normal.

OK start checking your gas mileage on a long trip then on short trips.
It is hard to tell on the gauges so fill it up and drive it and record mileage then refill it and check your mileage against galons it takes to fill it up.
MT

o.k.i'm gonna try that, but from what i told you do you have any idea whats wrong ?

Not really.
Check engine tune up first thing if it is using more gas then it used to..
Check actual gas mileage.
Post back actual gas mileage.
What mileage did it used to get when you got it?
MT

The tank was at 2 lines below the half mark, i filled the tank up and i put 7.51 gallons in there.

How many miles did it get since you last filled it up?
MT

MT-2500.........I have a half tank of gas and its reading that i dove 65 miles, shouldn't i have more miles than that with a half tank of gas gone ?

[MT-2500.........I have a half tank of gas and its reading that i dove 65 miles, shouldn't i have more miles than that with a half tank of gas gone ?

You can not go by the gauge on gas mileage.
Fill it back up and divide your miles drove by the no of galons it takes to fill it up.
Then post back MPG. and/or how many gallons it took to fill it up
MT

The tank was at 2 lines below the half mark, i filled the tank up and i put 7.51 gallons in there.

That is only about 9 MPG.
You need to geet it checked out.
You may need good tune up.
MT

What does a good tune up consist of, i changed the plugs, air filter, fuel filter, 02 sensor. The only thing i didn't change was the wires and by the way the car has very good power.

Ok you have done the basic plugs filters.
have a good repair shope look it over and put it on a good engine/trans scanner and check the fuel pressure system out see if any thing shows up.
The lose of power would be a good thing to look for.
Also check the back pressure on the cat.
Good Luck
MT

Thanks MT-2500 you have been very helpful, but what do you mean by checking the back pressure on cat ?

You have to put a pressure gauge on the exhaust before the cat and see if it has to much back pressure . If it does the cat is stopped up. One thing that will cause power loss.
MT

I understand that you want me to check the cat but i have power, probably more power than the average 3.1 malibu.

Sorry about that I miss read the post on power.
If the gas mileage is that low you need to get a good repair shop to look it over.
May with a scanner and diagnostic equipment the may be able to find out what the problem is.
Good luck
MT

How would i know if i need an 02 sensor in the back by the cat converter, would it show a code ?

Might and not show a code but codes do not say replace the sensor.
They say check it out.
I think you need to find a good repair shop and have them check it out.
MT

it is your fuel pump i just went through the same thing you think you are just getting bad gas milage but your guage is wrong. there is six little metal strips that read the electrical board on the fuel pump after so long these break off. a new pump is $300 and some change i got one at a junk yard for a $100 with 40k on it. when i took mine out it said the ank was empty when i put the other one in i really had a half tank. i got to thinking about it if you pull the pump out and bend the tabs to where they are touching the elec. board again you should be good for another 100k or so

. The fuel pump wiring , located at the lower right had side of the fuel tank,, has no cover or shield. It is exposed to road damage.( a design concern), & without the protective shield, the wiring can take a real beating.
b. Appy connecter dielectric ,&brush on wire protector, on the wiring. /cover with split flex .
:nono: Given the need for accurate impulses/ input from the sender to the module, you may have a faulty signal overpressering the system.
good luck!@ .

It appears my fuel pressure regulator is seeping gas. I cleaned it off really well and ran the car for 3-4 minutes and I see gas coming from under the lip. My Chiltons manual is confusing as to whether I need to remove the fuel rail on the 2.4. Step 3 says remove it, the final install step says, "if removed, reinstall the fuel rail. I too would like the real story, does the fuel rail need to come off???

Thanks,

It appears my fuel pressure regulator is seeping gas. I cleaned it off really well and ran the car for 3-4 minutes and I see gas coming from under the lip. My Chiltons manual is confusing as to whether I need to remove the fuel rail on the 2.4. Step 3 says remove it, the final install step says, "if removed, reinstall the fuel rail. I too would like the real story, does the fuel rail need to come off???

Thanks,


Some do.
But as always with new problem on a different car go to the proper forum and start a new thread on your car ans someone will help you.
MT