03 TJ losing power and dying

[k0m0d067]

You could just disconnect the O2's from the harness instead of actually pulling them. Easter and you wont break anything really determined to stayrusted put.

Nope, that wouldn't eliminate back-pressure caused by a plugged CAT (the purpose of pulling the upstream sensor )

Also, it cane out quite easily

 

[KCsTJ]

Any engine codes?

 

[k0m0d067]

Any engine codes?

After pulling the o2 sensor? Yes...0031 and 0132 (typical o2 sensor codes?

 

[astjp2]

Nope, that wouldn't eliminate back-pressure caused by a plugged CAT (the purpose of pulling the upstream sensor )

Also, it cane out quite easily

I have done it and it worked enough to diagnose. I subsequently took a steel bar and rodded out the cat and it fixed my problem. I dont care about emissions, I just wanted it to run good.

 

[k0m0d067]

I have done it and it worked enough to diagnose. I subsequently took a steel bar and rodded out the cat and it fixed my problem.

Yeah, that will probably be my solution as well

 

[KCsTJ]

After pulling the o2 sensor? Yes...0031 and 0132 (typical o2 sensor codes?

Those codes tell me your precats are shot. How many miles on the engine?

 

[dbbd1]

Those codes tell me your precats are shot. How many miles on the engine?

Those codes were only after he pulled the O2 sensor out (to see if the post cat was plugged).

 

[KCsTJ]

Those codes were only after he pulled the O2 sensor out (to see if the post cat was plugged).

Yes thanks for that dbbd1, I'm wondering if those codes are still valid. Had the same issue with my 05 Sport at 101k.
I've noticed the pre cats generally speaking are toast around the 100k mark.

 

[dbbd1]

I've noticed the pre cats generally speaking are toast around the 100k mark.

Hmm, bummer. I'm getting close...

 

[k0m0d067]

Yes thanks for that dbbd1, I'm wondering if those codes are still valid. Had the same issue with my 05 Sport at 101k.
I've noticed the pre cats generally speaking are toast around the 100k mark.

Intermittent check engine light prior to all this, but I didn't bother checking the codes as the light would go away after a day or two (and only recently learned the key trick)...checked codes prior to pulling the o2 sensor and it wasn't throwing any at all

Jeep has about 168,000km on it (a little over 104k miles)

 

[KCsTJ]

Bought my 05 Sport from a dealer with 101k. Within 50 miles I got CE lights. Dealer kept resetting engine codes till it sold.

The 4.0 was bogging down terribly.

Replaced the cats with Evan Fischer bolt on exhaust, and replaced both upstream 02 sensors.
Has run beautifully ever since.

 

[k0m0d067]

Alright...drove it around for several hours today with the sensor out, and it behaved just fine...

So as confirmation, I will reinstall the sensor in the morning and drive it again, and see if it dies again...

 

[Oldguy]

You could just disconnect the O2's from the harness instead of actually pulling them. Easter and you wont break anything really determined to stayrusted put.

THat doesnt let you know if the exhaust is plugged. You want the engine to breath easier

 

[Oldguy]

Alright...drove it around for several hours today with the sensor out, and it behaved just fine...

So as confirmation, I will reinstall the sensor in the morning and drive it again, and see if it dies again...

I had the same thing happen to my truck, Mine was in the pre cat, the small one on the down pipe. replaced everything from the manifold back. I also replaced the o2 sensors when I did it

 

[k0m0d067]

Mine doesn't appear to have the small cats...just the one larger one back by the transfer case

 

[Oldguy]

Mine doesn't appear to have the small cats...just the one larger one back by the transfer case

Thats good, just the cat back then