Help fuel pressure? Options

[bdog_v]

Maybe I should post this in the forced induction section, but anyway could someone please explain this.

-I am trying to test the fuel pressure I have at idle so I installed a fuel pressure gauge on the fuel return line just after it goes through the factory fuel pressure regulator and the then the hard line off the fuel rail finally connects to rubber hose.ing



-The reading i get is only like 3-4 psi. It should be around 40psi. Its not the gauge when I squeeze the return line after the gauge the fuel pressure jumps up to 40.




-I used this method to read fuel pressure on an fuel injected Isuzu I worked on and it worked great. Is the toyota celicas fuel pressure regulated differently?????? The car is running fine so I don't believe anything is wrong..... Help!!!!!!!

[Dr_Tweak]

Maybe I should post this in the forced induction section, but anyway could someone please explain this.

-I am trying to test the fuel pressure I have at idle so I installed a fuel pressure gauge on the fuel return line just after it goes through the factory fuel pressure regulator and the then the hard line off the fuel rail finally connects to rubber hose.ing



-The reading i get is only like 3-4 psi. It should be around 40psi. Its not the gauge when I squeeze the return line after the gauge the fuel pressure jumps up to 40.




-I used this method to read fuel pressure on an fuel injected Isuzu I worked on and it worked great. Is the toyota celicas fuel pressure regulated differently?????? The car is running fine so I don't believe anything is wrong..... Help!!!!!!!

You have to pick up the pressure from the high-pressure line BEFORE the regulator. After the regulator (return line) there is no pressure.

-Doc

[presure2]

you need to test it before or at the regulator.
putting it after isnt going to work because pressure is built behind the regulator, not after it.

[bdog_v]

Thanks guys after thinking about it for awhile longer I came to the same conclusion. But I still need some advice. I am trying to hook up a manually adjustable fuel pressure regulator but the stock one is actually part of the fuel rail so I do not know how to bypass it. On my isuzu it was seperate and I just replaced it, but on the toyota it is a pain in a**.

So can you:

-Simply add in a adjustable fuel pressure regulator after the fuel filter before the fuel rail. *The reason I thought this might work as I am only trying to lower fuel pressure not raise it.* " I don't think this would work as the factory regulator is still in place and would compensate for any changes made by the adjustable regulator"

Or can you disable the factory regulator somehow so fuel just flows through it? Maybe disconnect the vacuum line?


-How do people usuallly go about this with the regulator being mounted to the fuel rail when installing a manual regulator?

This post has been edited by bdog_v: Aug 6, 2009 - 1:38 PM