Replacing FPR?

[Lazzman]

I was wondering if it was very difficult to replace the Fuel Pressure Regulator on a 4.0 sohc motor?

Any tips or words of caution :scratch:

Thanks

 

[BrooklynBay]

First relieve the fuel pressure on the fuel rail. Push down on the button which looks like the same thing a tire would have (Schraeder valve). There are a few bolts to remove. Make sure that you lubricate the O rings with a fine oil. Replace the fuel filter too. Check for leaks when it starts up. The vacuum line goes on the top.

 

[Lazzman]

Thanks Brooklyn for the tips.

I am also concerned that the return line may be clogged. If it is not the FPR it could be the return line in my '98 sohc, causing the excess fuel to back up into the fuel rail.

How can I check the return line for clogs? Any tips?

Thanks again Bro.

 

[Turdle]

I would bet it isn't
to clog it would be a feat, and certainly clog the injectors--
Do the redneck thing-blow into it and listen for bubbles in your tank--

 

[Lazzman]

Ok, I will try that one out :scratch:

I recently had my injectors removed and tested and they were within 1% of factory spec.

I am always dumping a bottle of seafoam or Redline in at oil change time. I also replace my fuel filter at 30k mi incriments

JT what would cause an FPR to go bad??

 

[Turdle]

I think the diaphragm inside looses it's seal--

 

[aldive]

Not sure about a 98, but a 99 SOHC has no FPR ( returnless system ).

 

[Turdle]

Yes Al, he has one. 99 is when the change was made.

Now will you sleep better?

 

[Lazzman]

Ok, I am going to replace that sucka. I will let you know how it turns out JT.

Though I do first want to test the fuel pressure.

JT why does an engine need a Fuel Pressure regulator anyhow? Aren't the injectors only going to pump the amount of fuel that they are capable of anyway, such as 19lb an hour? I thought the computer and the injectors controlled fuel flow?

 

[BrooklynBay]

The fuel pressure regulator presets the amount of pressure the fuel injectors will see. The computer controls the duty cycle (on/off time ratio) of the injectors, but not the flow rate. Think of it as a valve. It will only let a predetermined amount of fuel pass in a predetermined amount of time.

 

[Lazzman]

Ok, that makes sense.

Thanks