L98 TPiS Adjustable Fuel Reg
Thread Starter
Le Mans Master
Joined: Jul 2001
Posts: 6,252
Likes: 2
From: Silicon Valley Kalifornia
Re: L98 TPiS Adjustable Fuel Reg (vinnies87)
Hopefully...been having some troubles with A/F ratio running lean and was checking the fuel pressure and it is like approx. 16-20lbs. I know that stock pressure should be 34-39lbs with vacuum line disconnected. So I tightened the screw up as much as I can and the pressure seems to be even less than 16-20lbs :eek: ...so hence my question.
Burning Brakes
Joined: Oct 2001
Posts: 1,033
Likes: 0
From: Tracy California
St. Jude Donor '05
Re: L98 TPiS Adjustable Fuel Reg (GRX)
Clockwise should increase pressure (in to increase-out to decrease). What fuel pump do you have in there? I wouldn't run it anymore till you solve this, your fuel pressure should never be that low while it's running.
The regulator may be hosed? in theory it could cause an internal leak. Ofcourse a plugged filter might mimic this as well.
Good Luck
Kelvin
The regulator may be hosed? in theory it could cause an internal leak. Ofcourse a plugged filter might mimic this as well.
Good Luck
Kelvin
Thread Starter
Le Mans Master
Joined: Jul 2001
Posts: 6,252
Likes: 2
From: Silicon Valley Kalifornia
Re: L98 TPiS Adjustable Fuel Reg (88-406)
Well, there isn't fuel coming out of the regulator's vacuum fitting so the diaphram isn't comprimised. The fuel pump is "new" but was sitting for about 3-4yrs without operation. I changed the fuel filter before running it a few weeks ago but because the car has sitting for a long time maybe debris accumulated in the filter? I did "clean" the tank before starting the car. :(
Burning Brakes
Joined: Oct 2001
Posts: 1,033
Likes: 0
From: Tracy California
St. Jude Donor '05
Re: L98 TPiS Adjustable Fuel Reg (GRX)
So are you able to adjust FP at all? Your pressure line goes straight to the rail right? Maybe you can rig a gauge to the pressure side for a very quick test. Besides if the pumps bad atleast we dont have to pull our tanks like the Ford guys.
KM
[Modified by 88-406, 6:32 PM 2/3/2004]
[Modified by 88-406, 6:33 PM 2/3/2004]
KM
[Modified by 88-406, 6:32 PM 2/3/2004]
[Modified by 88-406, 6:33 PM 2/3/2004]
Burning Brakes
Joined: Feb 2003
Posts: 1,212
Likes: 0
From: OH
Re: L98 TPiS Adjustable Fuel Reg (88-406)
If you tighen the regulator too much it actually starts to stop flow, back out a little and see if you get the pressure back. I noticed this with my Holly FP regulator, kept on having to crank up the pressure, ended up my filter was getting clogged. Once I got to the extreme it actually got lower by tighening.
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Le Mans Master
Joined: Mar 2002
Posts: 5,300
Likes: 4
From: Mississauga, Ontario Corvettes were built to be driven...not trailered
St Jude Donor '07-'08-'09
Re: L98 TPiS Adjustable Fuel Reg (GRX)
MJ, invest in a small pressure gauge which you install directly into the passenger side fuel rail near the back...its always good to know what pressure you're running and its looks cool too!!! :cool:
Burning Brakes
Joined: Sep 2001
Posts: 981
Likes: 0
From: Anderson South Carolina
Re: L98 TPiS Adjustable Fuel Reg (Quik86)
Be careful when adjusting the fuel pressure regulator, the screw came out on my L98 and the fuel pressure dropped at wot, this almost cost me a new motor, I got lucky, it only blew a head gasket.
