Long Crank Before Start?

[Leeann]

Yep, KOEO (key on, engine off).

 

[tjkj2002]

Haha that is what I thought. What is the correct procedure for testing the fuel pressure at the rail?

if I'm thinking correctly you put it on the valve with the car off and turn the car to the on position and it should be reading between 40 and 45 psi?

Yes test at the test port on the passenger side fuel rail,for the KJ it's 49psi(+/- 5psi) with engine running at idle at full operating temp.The fuel pressure should stay above 30psi for at least 5mins after the engine is shut off and key removed.The KJ uses a "returnless" system so only 2 things will cause the pressure to bleed off fast,injectors or the check valve in the pump.It's totally normal to have zero fuel pressure on a fully cold engine like leaving the pressure tester hooked up over night.




You'd need a more advanced level fuel pressure test kit to tie into the fuel rail connector and use a shut off valve to test for either leaking injectors or a leaking check valve in the pump.

 

[bmrrwolfe]

Yes test at the test port on the passenger side fuel rail,for the KJ it's 49psi(+/- 5psi) with engine running at idle at full operating temp.The fuel pressure should stay above 30psi for at least 5mins after the engine is shut off and key removed.The KJ uses a "returnless" system so only 2 things will cause the pressure to bleed off fast,injectors or the check valve in the pump.It's totally normal to have zero fuel pressure on a fully cold engine like leaving the pressure tester hooked up over night.




You'd need a more advanced level fuel pressure test kit to tie into the fuel rail connector and use a shut off valve to test for either leaking injectors or a leaking check valve in the pump.

Well I performed a pressure test and with the jeep in the ON position not running pressure was 53 psi. Once started, the pressure went to 59. Stayed constant while I let it idle for 15 minutes. Revved it to 2500 rpms a few times and stayed at 59.

Turned it off and pulled the key and pressure fell to 55 psi and remained there for 10-15 minutes with no loss before I pulled it..