EFIDynoTuning Forum

DLeach,

Thanks, my Lincoln Mark VII had a similar problem - a hole in the hose from the pump to the tank hat. I pulled the tank, replaced the hose with the special immersion spec hose and installed a Walbro pump and a BBK adjustable FP regulator. To my wonderment, it still won't hold pressure and I wonder if the expensive BBK regulator doesn't have a residual pressure valve. Or maybe the new pump's residual pressure valve is bad. Other than that, it runs fine.

The truck never misses a beat, but has not had its tank pulled yet, so I can suspect the tank hose, pump valve or the replacement FP regulator.

Therefore, I was trying to band-aid both crappy-starting vehicles with more pump run time before start.

Decipha - Thanks again for your advice; however, I didn't understand "pre-tune info" .....

Heemie .....

Decipha,

Yes, certainly you are right - the NAPA regulator is junk. You also confirmed my guess that I can't increase the pump run time.

Do the Motorcraft replacement FP regulators have the proper residual pressure valve?

Which aftermarket adjustable FP regulators aren't junk and do have the valve?

Thanks for your assistance Decipha. Your write-ups have helped me get my 398 CI CBAZA truck and 331 CI Mark VII GUF1 dialed in and running smoothly.

Heemie .......

When the key is turned on, the fuel pump runs a stock time of about two seconds and then shuts off.

My replacement fuel pressure regulator does not keep the system under pressure after shutoff like a factory piece.

How do I increase the fuel pump run time in CBAZA J4J1 when the key is ON, before I start the engine?

Using Binary Editor.

Thanks!

Heemie ......