failure to start after warmed up

[QB93Z]

Fuel rail pressure is a variable. The system is designed for a constant pressure differential across the injector. The pressure in the Intake Plenum varies with throttle position, from high vacuum at idle to atmospheric pressure at full throttle. Therefore the Fuel Pressure Regulator is connected to plenum vacuum and adjusts fuel rail pressure to follow the changes.

As a rough check fuel pressure varies from 40 to 50 psi under normal conditions. The highest pressure you would see is with fuel pumps running, engine off, Ign ON/Engine OFF.

The Field Service Manual gives exact parameters for testing and evaluating the FPR.

Jim

[A26B]

Ty,
My first replacement pump choice would be Delphi FE0039 $49.79 Rock Auto

My Second Choice would be Airtex E3240 $38.79 Rock Auto

I would also recommend replacing all of the plastic hose clamps with ss worm clamps. Be sure to rotate the gear housing to the inside to make it easier to install.

Jagdpanzer & QB93Z are spot on. QB93Z probably has more real-world experience than anyone, considering the incredible trips he & Lindy have taken in ZR-1's and the years of volunteer support of time & facilities he has given to the WAZOO group. I'm proud to know them both personally as great friends.

[orthodoct]

Thank you, Captain! You were exactly right. I just talked to Jerry an he told me that you were great friends. He and I have corresponded quite a bit over the years. Going to order a new pump from him tonight. Put in a friend request, if you don't mind. Will update once the new pump is installed to bring some closure to this thread.
Best regards.
Ty

[karlaw]

Thanks orthodoct, I am going out to inspect both my cars. I am also anxious to get a fuel pump jumper to try to help diagnose my no starts.


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[orthodoct]

Good luck, my friend.
Ty

[orthodoct]

Originally Posted by orthodoct

Good luck, my friend.

Ty

Sorry for long delay. Had a KNEE REPLACEMENT five weeks ago. Did a couple of thousand of them before I specialized my practice to shoulder and knee arthroscopy. Hurt like HELL and takes forever to get over. Finally well enough for some standing up tinkering. Checked fuel pressure below 176 and read 42psi. Ran to operating temp which is 192 with Mark's chip. Shut down and restarted fine. Waited 15 minutes attempted restart. Wouldn't start. Fuel pressure varied from zero to ten psi. Hobbled around a couple of weeks and changed pump assembly yesterday. Scared the hell out of me. Ran fine on warmup, but when I punched the secondaries in neutral, I killed every mosquito in the neighborhood. Scared that I had a broken valve or ring or something, but smoke symmetrical from both pipes and no oil odor. Dawned on me that I had disconnected negative battery terminal prior to pump change (I'm a private pilot as a hobby and burning to death ain't high on my bucket list) and I think that computer settings went to rich default settings and car hadn't been started since before my surgery so old gas in secondary injectors, "blowing out carbon", etc. ANYWAY, went for a short drive to reset everything (with GOLDCYCLON's trusty bypass jumper in my console just in case) and everything runs JUST FINE, problem solved. I promised to try to close this thread once less crippled and I'm glad that it had a happy ending. As usual, thanks to the brilliant guys with the Registry with whom I am proud to be associated. Special thanks to my friends the Captain, GOLDCYCLON, and of course Jerry without whom many of our cars would no longer be on the road.
Ty


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[GOLDCYLON]

Glad you got her up and running again. Take it easy on the knee. GC

[orthodoct]

Originally Posted by GOLDCYLON

Glad you got her up and running again. Take it easy on the knee. GC

Thank you, my friend!
Ty


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[5ABI VT]

Happy to hear it was solved.

[orthodoct]

Originally Posted by 5ABI VT

Happy to hear it was solved.

Thank you, me too!!


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