Hi. I have a quick question that hopefully someone can answer. I have a 1971 Toyota Landcruiser with a 1992 350 TPI. I had to replace the fuel pump and at the same time switched out the fuel pressure regulator. Now, when I turn the key on, my fuel pressure jumps up to about 70 psi. It's about 40 psi while cranking and then once the engine starts, it jumps up to 90 psi and leaks from the lower injector o-rings. I am trying to determine if the fuel pressure regulator is causing this or if the return line is clogged or pinched.

Thanks for any suggestions.

 

It could be either. If you can safely disconnect the return line near the engine compartment and route it to a catch can, you will be able to determine whether the regulator is flowing through its return port. If so, and the pressure the pressure is normal, the return line back to the tank itself is suspect. If the regulator is not flowing to the return line, the regulator and/or fuel rails will need to be checked.

 

Thanks Vader!

I had good flow on the return line. I just ended up adjusting the FPR to 45 psi and it is running fine now. I guess someone had adjusted it before I installed it and it was a little too far out of whack.