Catalytic converter not ready when smogging

[Logans99TJ]

First issue I've had smogging a vehicle.
I took it in to be smogged a few months ago and the only issue I had was it failing because I had just replaced the battery, so i was going to have to bring it back. When I came back a month later it would not pass because the "cat" was not ready. I figured the huge leak in the exhaust manifold could be the issue. So I replaced the manifold...sounds a lot better. (side note...shop around, I was shocked at the number of mechanics wanting over $850 to change it.)
Took it in today, same issue, cat not ready. No check engine light. I am debating just changing the cat or replacing the whole exhaust system as its 21 years old.
Thoughts?
I was also thinking about just changing the o2 sensors and seeing if it would pass...but like I said, no check engine light.

 

[Rob5589]

Generally, you will need to put about 300ish miles on the vehicle any time the computer is reset; eg, battery disconnected. I had the same issue with another vehicle. Yep, CA blows.

 

[Andersen24]

Logan.....read the last page of this thread and here is a link to the drive cycle information. Also if yours is a 99, you are allowed to have one of the three readiness lights not reset. Starting in 2000 all of the readiness lights must not illuminate.

 

[Mr. Bills]

The "universal OBDII drive cycle" linked above may or may not work with your Jeep.

For the specific Chrysler drive cycles for each readiness monitor see this link: http://www.obd2.com/support/reprog/downloads/chrysler/chry-imset_procedure.pdf

There is a use note in the Chrysler instructions suggesting that one use the specific drive cycles listed for each monitor rather than rely on the "all monitor" drive cycle.

 

[Andersen24]

The "universal OBDII drive cycle" linked above may or may not work with your Jeep.

For the specific Chrysler drive cycles for each readiness monitor see this link: http://www.obd2.com/support/reprog/downloads/chrysler/chry-imset_procedure.pdf

There is a use note in the Chrysler instructions suggesting that one use the specific drive cycles listed for each monitor rather than rely on the "all monitor" drive cycle.

Thanks Mr. Bills - I meant to link that one and had too many pages open .....my link talked about the number of readiness codes allowed - and yes gave the universal. The Chrysler one you reference is spot on!

 

[Logans99TJ]

Thanks Mr. Bills - I meant to link that one and had too many pages open .....my link talked about the number of readiness codes allowed - and yes gave the universal. The Chrysler one you reference is spot on!

Thanks, had no idea there was a process.

 

[Logans99TJ]

The "universal OBDII drive cycle" linked above may or may not work with your Jeep.

For the specific Chrysler drive cycles for each readiness monitor see this link: http://www.obd2.com/support/reprog/downloads/chrysler/chry-imset_procedure.pdf

There is a use note in the Chrysler instructions suggesting that one use the specific drive cycles listed for each monitor rather than rely on the "all monitor" drive cycle.

Thanks, I have driven around but now will drive with purpose!

 

[Logans99TJ]

Changed the CAT sensor this afternoon.
I was really dreading this thinking about taking the skip plate off.
I had applied some PB blaster a couple times last week since it worked so well on the upstream o2 sensor. Before tackling the project I thought I'd just crawl under to see what was what...due to the sun beating down on the passenger side of the TJ I went in from the drivers side. To my surprise I was able to easily reach over the drive shaft and get the o2 socket wrench on the sensor...a little pushing on the wrench and BAM, it came out with ease.
I figured this would take a couple hours but ended up taking 10min. Thanks for all the advice.
Here is a pic of the old sensor...don't know what is normal for discoloration.

 

[rbkelley89]

Sorry to bring this up from the dead but I've been working on this same issue for a few weeks. So did changing the O2 sensor fix the cat? I ran diagnostics on my jeep to see but the O2 sensors are passing and the cat says incomplete. I've tried the drive cycle a couple of times to no avail. Other threads have mentioned something about 40 cold starts to get it ready?

 

[Mr. Bills]

The link for the proper Chrysler drive cycle procedures is in Post #4.

The [insert large number] driving cycle references are Internet nonsense.

 

[Logans99TJ]

View attachment 88862

Sorry to bring this up from the dead but I've been working on this same issue for a few weeks. So did changing the O2 sensor fix the cat? I ran diagnostics on my jeep to see but the O2 sensors are passing and the cat says incomplete. I've tried the drive cycle a couple of times to no avail. Other threads have mentioned something about 40 cold starts to get it ready?

I must have missed this post! As of today I am still unable to pass smog due to CAT monitoring. So I'm guessing that my next step is to change the CAT.

 

[Logans99TJ]

UPDATE: Passed smog! Don't know why it took so long for the cat monitor to reset...but I followed the steps posted by Mr. Bills and took a nice 40 mile drive on the interstate, check the OBD2 scanner and it said "ok" so I got it down to the smog guy and bada bing.
Thanks for the comments and help!
Up next steering stabilizer!

 

[Mr. Bills]

. . . I followed the steps posted by Mr. Bills. . . .

Actually, the link to the Chrysler drive cycle procedures was first posted by @mrblaine. Thank him.

https://wranglertjforum.com/threads/unable-to-pass-emissions.1138/#post-16402