When it comes to maintaining fuel pressure, the FPR is only part of the equation. Your problem could lie in the fuel pump itself.

 

but the problem started with replacing the FPR .. so it's quite likely the FPR?

 

I found a mopar 37341ZY via ebay.com (the one on amazon doesnt ship international) ..

https://www.ebay.com/itm/For-1997-2...Jeep-Wrangler-Fuel-Pressure-Regulator-Mopar-37341ZY-1998-2001-1999/293373373893

it's $190 including shipping and tax and should take 14 days to arrive ..

amazon ships via UPS within 3 days express for just $30 ... but yeah.. no dealer on amazon has it :nonono:

 

If your only issue is maintaining fuel pressure after shutdown, consider just adding a fuel line check valve near the tank. Super cheap, and doesn’t require lowering the tank.

 

Also consider that folks who have done that experienced ruptured fuel lines due to heat expansion.

 

went ahead an ordered the mopar one.. I'm no fan of implementing workarounds instead of fixing the known source of an issue.. in my case a defective FPR

 

had the FPR replaced today with a original Mopar one.. and guess what .. same problem. If the engine is shut of for 5+ minutes it requires 4-5 times turning the key (and hear the fuel pump running for a sek) before I can start..

that problem appeared first after replacing the original (leaking) FPR with a $60 buck one from amazon... so how can it still exist after replacing it again with an ($150) from Mopar?

I did the blow-thru test with the mopar I've read about in the forum and it was definitely blocking the way back.. as it's supposed to

 

I've just tested the original 20 year old FPR, which was replaced due to the broken O-ring fuel leek with a tire pump at 20 psi and air blows thru.

Did the same with the first $60 FPR I got new from amazon and got the same result.. air blowing thru even much more easy than the old one.

Of course I can't test it with the current installed Mopar one, but since the problem still exists I probably got a broken Mopar one too and have a run on broken FPRs?

 

I've just tested the original 20 year old FPR, which was replaced due to the broken O-ring fuel leek with a tire pump at 20 psi and air blows thru.

What do you think you are testing with that "test?" There is nothing to stop air from "blowing through" an uninstalled FPR.

 

went ahead and ordered the complete Delphi assembly. Wish me good luck that it's the last time lowering the tank. I'll keep you guys posted

 

installed the whole Delphi assembly today.. works like a charm.. should have done that in first place and save a couple hundreds of dollars.. hope it stays like that

 

it was working fine for 3 days.. today back to old problem.. I guess I have to live with it from now on.. I have no mood any more to order another Delphi assembly and replace it again.. few people on amazon reported exactly the same problem with the Delphi assembly (working fine for few days and then back to problem) - why I didn't want to replace the whole assembly in the first time

 

Whats the chance that fuel is bleeding past one of the injectors?

 

I would expect gas smell. also the issue appeared the second after replacing the original FPR (while I replaced it again, but without success) and was fixed for few days after replacing the whole assembly with Delphi - so I don't expect the issue to be somewhere else.

I've now ordered an original Bosch assembly from a junkyard in the US via ebay plus a new original Bosch pump from Amazon .. my last hope. I'll keep u guys posted

[UPDATE] just ordered new fuel injectors too just to be save