2002 4.0 Crank but no start

[Pjhanlo]

Hey guys, I just developed an issue with my 2002 4.0 automatic.

Jeep runs and drives great, starts just fine in the morning. But say I park at a gas station and come out to start it 5 minutes later? The jeep will crank endlessly but will not fire up. If I wait another 10-15 minutes it will fire up just fine on the first crank.

-Battery voltage is good,
-Connections are good,
-All fuses are good,
-Replaced crank position sensor (I heard this is a known issue apparently?)

I tested the fuel pressure today at the rail and it’s reading 50psi when the key is in the on position. With the engine running it’s reading 100psi. It looks like my fuel pressure is ridiculously high. Is this the cause of my start issues? And does anyone know how to diagnose and correct this high pressure issue?

Thank you,

 

[macleanflood]

Pressure regulator is in your fuel pump.

You can replace just that regulator or the entire pump assembly.

-Mac

 

[CharlesHS]

Please show me where the fuel pressure regulator is located.

 

[macleanflood]

I believe part 5 doubles as a pressure regulator.

I rebuilt my pump assembly but the new Brazilian Bosch pump failed in two weeks. Then the plastic frame got too brittle and broke. Ended up with a Brute Power pump assembly from Rock Auto.

V

Thread 'How to replace your fuel pump without replacing the whole assembly'

Dec 21, 2021

Ok, I figured I'd post this here since I haven't seen it anywhere else. I've been chasing a hard start issue on my tj and got down to the in tank pump. I knew the sending unit was still good, but wanted the peace of mind of having a new pressure regulator and pump. I also didn't want to fork over ~$200 for a new assembly when I knew I could find a pump and regulator for much less. I didn't take pictures during the process because I'm a dumba$$ and this was the last thing I did on a Saturday so I was ready to be done. This only applies for 97-04 TJ's I believe. Assuming you've managed to...

• vrtillman
• Replies: 21
• Forum: TJ How-to Guides

• 

-Mac

 

[Pjhanlo]

Pressure regulator is in your fuel pump.

You can replace just that regulator or the entire pump assembly.

-Mac

I’ll replace the regulator and update you guys on the fuel pressure/ cranking issue

 

[Pjhanlo]

Replaced the fuel pump + regulator and the problem cleared up! Must’ve had a bad unit, it was only 3000 miles old.

Don’t buy Amazon parts. Thank you everyone

 

[macleanflood]

What fuel pump assembly did you go with?

-Mac

 

[Larry L TJ]

What fuel pump assembly did you go with?

-Mac

following