Ok so i have a 2000 4.0 that tries to cut out on me while driving and when i come to a stop it will idle super rough and try to stall. Idle will drop all the way to 400 rpm. I'll take off again and it will be really bogged down like it running rich and can hear it back fire in the intake. Every now and then it will trip every single o2 code and i've replaced both up and downstream o2s. Still no luck. and i have also pulled the iac and cleaned it very throughly. Any suggestions?

 

How low is the fuel pressure?

 

I haven't checked the fuel pressure on it.

 

Look into fuel pressure and then report back.

How recent has the ignition/grounding systems been refreshed?

Look into fuel pressure first, though.

 

Check O2S Heaters fuse in the PDC, marked in the pic as 'O2S RELAYS'.

 

Thanks a lot guys! check the fuse and it was blown. Haven't had a chance to drive it yet.

 

As a rule of thumb, when a fuse blows there's a reason. Now, that's in the real world; however, you're dealing with a Jeep, which means a fuse will blow just because it wants to. LOL

If the fuse blows again you will need to dive ino the root cause.

Let us know how it works ot.

Cheers.

 

Well i bought it back in august and the guy told me it had a bad o2 which i thought was no big deal. And when i went to replace them i saw the drive shaft some how jumped up and bit the wiring harness to the downstream o2. So I made a new o2 harness and what not and it worked fine for a while. idk why i didn't check the fuses haha