Trying to get Through CA smog... A couple issues: Monitor, Code and 02 readings pics

gulkana

New member
Any help would be MUCH appreciated!
I am the new owner of a very much neglected 2002 4x4. Ive slowly been going over the motor and fixing major/minor repair issues. compression is good, truck runs smooth. Initially when I first scanned the rig I had the upstream 02 code. I replaced the upstream 02 with a spiffy Denso and cleared that out. I loaned my scan tool to a friend and I thought I had cycled the rig enough to complete the Catalyst monitor.. but it didnt and the smog place failed it due to that. SO now I am trying to cycle this thing by driving it without plates and a one day moving permit LOL! Ive driven about 40 miles and sort of going through the cycling procedure as best I can relative to where I live.
I got my scan tool back and ran it..There is a pending code P0420 (see pics) No exhaust leaks going on and the cat looks to be in decent shape, no rattles or leaking. I did not replace the rear downstream sensor but I have that ordered. My question is in the photo below the 02b1s2 line is up and down. I don't know what that means. I believe it is suppose to be a straight line. My questions are: How long before the system sets from the cleaning code / battery disconnected procedure? And what is the cause behind the up and down 02b1S2 reading shown in the photo below? The upstream sensor is reading correctly according to my limited manual.
CA smog needs to see the Catalyst Monitor complete the EVAP they dont care about.
thanks for any help! Greatly appreciated!
 

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My brain is a bit hazy on this, but by any chance is your o2 sensors plugged into the correct connector? The front on the front and rear on rear (if that's even possible?). If they are connected correctly then it might be one of the 2 cats or both being bad? Also is your 4runner ca emissions or federal? IIRC ca emissions 4runners have 2 cats instead of one.

Your front o2 is doing what the rear o2 should be doing and vise versa. Usually the engine is constantly adjusting its afr. Thus the front o2 is up and down. While the rear is a steady voltage after warm up.

Also the evap will pass when you have 3/4 of a tank or fuller......usually.
 
My brain is a bit hazy on this, but by any chance is your o2 sensors plugged into the correct connector? The front on the front and rear on rear (if that's even possible?). If they are connected correctly then it might be one of the 2 cats or both being bad? Also is your 4runner ca emissions or federal? IIRC ca emissions 4runners have 2 cats instead of one.

Your front o2 is doing what the rear o2 should be doing and vise versa. Usually the engine is constantly adjusting its afr. Thus the front o2 is up and down. While the rear is a steady voltage after warm up.

Also the evap will pass when you have 3/4 of a tank or fuller......usually.
This 4runner came from Washington, at least it had Wash. plates on it when I got it. But it has two cats. It looks like the sensors are plugged in correctly and in the correct spot. I'll do a heat gun test on the cats today and maybe attach my shop vac in there and see if there are any leaks or strangeness going on.
 
I just went through this on my 2000 in CA. I drove hundreds of miles and still couldn't get the catalyst "code" to clear. So I went to YouTube and google and came up with these 2 solutions and my T4R passed!

1. Buy a bottle of CATACLEAN from your local auto parts store and follow the instructions on the bottle. Lots of videos online if you want to dig deeper.

2. This video in combination with the Cataclean cleared the catalyst code and my 2000 T4R passed
https://youtu.be/BuZYAy_xi0E?si=Oe7OcAkd6Jz8Vvo_

I tried so many different things and drove so many miles, these 2 things are what got my rig to pass.

Good luck brother
 
I just went through this on my 2000 in CA. I drove hundreds of miles and still couldn't get the catalyst "code" to clear. So I went to YouTube and google and came up with these 2 solutions and my T4R passed!

1. Buy a bottle of CATACLEAN from your local auto parts store and follow the instructions on the bottle. Lots of videos online if you want to dig deeper.

2. This video in combination with the Cataclean cleared the catalyst code and my 2000 T4R passed
https://youtu.be/BuZYAy_xi0E?si=Oe7OcAkd6Jz8Vvo_

I tried so many different things and drove so many miles, these 2 things are what got my rig to pass.

Good luck brother
I'll definitely give that a shot! Thanks for this!
 
This 4runner came from Washington, at least it had Wash. plates on it when I got it. But it has two cats. It looks like the sensors are plugged in correctly and in the correct spot. I'll do a heat gun test on the cats today and maybe attach my shop vac in there and see if there are any leaks or strangeness going on.
All 01/02 4Runners have 2 cats and the front AFR / rear O2 sensor setup. California got that setup in '99. All others (96-00 Fed and 96-98 CA) got the single cat and F/R O2 sensors.

The rear O2 sensor should not be going up and down so quickly. The signal should be 'smoothed out' by the catalytic converter, so this does hint that the cat is not working well. The front AFR sensor should have a nearly constant signal whenever the engine is running in closed loop (so, not at startup and not when at/near full throttle).

It is worth a try to use the 3k while stopped trick to see if you can get the O2 sensor monitor to set. You shouldn't need a tailpipe test for '00+ vehicles, though if this is a smog check for coming into the state, it may be more involved.

-Charlie
 
This may not help, but I did some work on my CA 2000 that involved disconnecting the battery a week or so before my smog was due (lost all data) and and went through the drive cycles like crazy trying to set Cat readiness with no luck. I believe it was driving at exactly 60MPH for miles that finally seemed to do it. I will try to find that thread and report back. You may have another issue but it can't hurt.

Edit - if you haven't done so recently, a cheap and easy thing to do is clean your MAF sensor with a can of CRC MAF cleaner. Had a positive effect on P0420/CAT/SMOG issue here: P0420 code? READ THIS BEFORE REPLACING CATALYTIC CONVERTER!
 
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