My 3rd Gen's CEL history/sensors

[T4R_Finally]

I posted last week about my P0420 (CAT deficiency) code and got mixed reviews as to whether my downstream O2 sensor could be bad or if it's a poisoned CAT. Either way, I thought it was worth it to go ahead and replace the sensor and see what happens. Ordered one and it will be here tomorrow. Just went out and PB Blaster'd the old one to get ready for replacement.

Today, I was finally able to get the detailed service records to show up on the owner's website. Aside from the service receipt I found in my glove box showing a CEL back in march of this year for some sort of accelerator sensor issue, I found 2 other CEL issues reported. In January of 09, a P0171 code was thrown and the MAF sensor was found to be dirty. MAF was cleaned and code cleared. Prior to that, in late 08, codes P1135, P1130, and P1125 were thrown. The Air Fuel sensor was replaced and codes cleared.

Not sure why I'm posting this other than I'm hopeful that a new O2 sensor will make my P0420 go away. And seeing other CEL's addressed by sensor cleaning and/or replacement, gives me a little hope at least. When I was underneath verifying that I had CA Emissions, I could tell the AF sensor was not as old as the vehicle. Now I know how old at least.

The previous owner tells me the CEL wasn't coming on before selling to me. But I find it a bit to coincidental that I bought it and it came on for me, 3 times, once within the first 50 miles of driving it, with the same code.

I just hope I don't find myself buying a new CAT instead of Christmas presents this year.

 

[spotter10]

Thanks for your post. My CAT was stolen from my 2000 4runner a couple weeks ago and since having it replaced I've been trying to collect as much info on what problems to look out for.

So far there have been no problem codes and no issues other than it feels like there is somewhat lower power although I could be paranoid. I've been thinking about replacing the rear O2 sensor and see if that improves anything.

Anyway, thanks for your post.

 

[TheDurk]

Thanks for your post. My CAT was stolen from my 2000 4runner a couple weeks ago and since having it replaced I've been trying to collect as much info on what problems to look out for.

So far there have been no problem codes and no issues other than it feels like there is somewhat lower power although I could be paranoid. I've been thinking about replacing the rear O2 sensor and see if that improves anything.

Anyway, thanks for your post.

The rear sensor has zero effect on performance. All it does is set codes. So I expect you will be disappointed.

 

[T4R_Finally]

Spotter, did you put on a different kind of CAT or have anything changed? If you aren't getting codes, don't touch the sensor. It certainly has nothing to do with any loss of power that I know of. My guess is you are just paranoid, unless maybe you got a CAT that's more restricted than what was on there before.