computerpulse

2000 Jeep XJ. 4.0L loosing fuel pressure after shut down. Replaced the fuel pressure regulator ontop of the fuel pump. Still happening. I was told to replace the entire fuel pump, but don’t see that being the problem, has good pressure while running.

BlueRidgeMark

There is a check valve that is supposed to keep the pressure up. I don't know where it's located on a 2001. If it's integral to the fuel pump, then you need a new fuel pump.

By the way, it's "losing" not "loosing". "Loose" rhymes with "goose", and "loosing" rhymes with "goosing", which is not what you want to do with a fuel system.

PatHenry

Cruiser has the 2000 FSM and parts catalog on his website (www.cruiser54.com - technical manuals link), it should clearly show where the check valve is and procedures for replacement.

If you've already dropped the tank once, at least it's a bit easier the second time - in my experience anyway. I had to replace the pump and tank skid plate on my 00 TJ - do your research on pumps if you do need a new one, some brands are better than others and you don't want a bum pump.

computerpulse

It’s called voice recognition sir or ma’am, but thanks for the English lesson, I believe the check valve is in the part I installed however I will double check that.

Cummins93

If any part of the system has a small leak the pressure will bleed off. Rusted, damaged/rub through on the line. Injectors that have debris in the pintle seat can leak slowly.

cruiser54

Agreed^^. How fast does it leak down after shut off?
This can be diagnosed by pinching the fuel line ahead of the "check valve". See if it still leaks down. If so, it's not anything related to the pump area but has injectors not seating completely.

Sasquatch in ks

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