Lizard928

The FPR do not have any electrical connections that you can check,

there is a vacuum line on the FPR first thing to do is pull that line off and pressurize the fuel system, it should not leak ANYTHING out of it.

w3lfd

FP test is going to be simple (pull the bolt off at the end of the right hand rail and install pressure guage, careful because there is fuel under pressure here.).

The regulators run strictly on vacuum. Checking the pressure at the end of the rail will tell you if either of the regulators are bad.

What you do is hook up the pressure guage, pull the fuel pump relay and jump 30 - 87 connectors to run the fuel pump.

Then, note the pressure. Clamp off the return line (to tank) of the regulator that you are NOT checking. If the pressure rises significantly, the non clamped regulator is not allowing fuel to return to the tank and more than likely needs replaced.

Another thing off the top of my head, and i may be way off base on this, I think the brain runs injection as 2 banks, and it could be the ecu that is hosed. It would probably pay off to test your car with a known good ecu if the FP regs check out okay.

w3lfd

Vacuum is definitely something to check first.

tailpipe

before u get to nuts on things here u might want to check and make sure the timing belt hasn't jumped a few teeth old unadjusted timing belts r bad for that and if they go to far they can load up the cat with raw fuel and set fire to the car seen two cars already torched that way

porsche 928 RI

i went to harbor freight and picked up an fp tester hopefully i will be able to do the tests tonight after work

w3lfd

I would definitely consider this also. Do you know the condition of the TB?

porsche 928 RI

i was browsing through the service history and it turns out it was replaced last may, and it does look brand new

The_Remora

Make sure it was installed properly and not a tooth off

stealth

Isn't it great having that S. Attleboro Harbor Freight there now?

I love my new aluminum 3-ton racing jacks (I bought one and liked it so much I bought another). Hope they last reasonably.

stealth

It should be retensioned 1500 miles or so after a replacement because a new belt can stretch. Better check tension and cam timing if those who know more than I do are suggesting it.

porsche 928 RI

harbor freight is a god send lol, once im done with the pressure checks i will definatly take a look at the timing belts tention i baught the same 3 ton jack too!!

porsche 928 RI

i just finished checking fp regulators the left one is showing 38psi or 2.5 bar so i think its fair to say that was the problem

w3lfd

What does the FP show with no return lines clamped? I don't have the manuals here at work, but 38 psi doesn't sound too far off base (maybe even on the low side). I'll check it when I get home.

porsche 928 RI

i just got done checking the right side, the exact same readings as the left?? strange, somethine else must be the cause

porsche 928 RI

with no clamp the readings are exactally the same, its too strange for the entire left bank to have bad injectors?