P0420- My bad luck continues....

Well I'm in the mood to complain so you can all suck it up and listen to me

I've been searching for a 2000-2002 Tundra for almost a year but gave up hope due to all the problems they had due to rust. After a month of moping around, I decided to give a Tundra one last shot because I found one with a new frame. Turns out, it checked out perfectly except it needed a new timing belt and tires within a year. I got a great deal on new tires (Hankook Dynapros for $500- installed and aligned) so I had them put them on. The dealer is about an hour away so I called on friday to make sure I could pick up the truck Saturday. They said the tires weren't in stock so they had to be shipped form the warehouse. So now I will get the truck sometime during the week.

I had a potential buying coming to look at my Taco Saturday around noon but I decided to postpone that since I can't be without a truck. That person was planning to buy it on the spot for $9,600 if it checked out mechanically (I was sure it would).

Since I still only had the Taco, I was driving around in it last night around 9PM when the check engine light comes on. I go home, check the oil level, the gas cap and don't see any problems. Today (Sunday), I had it scanned at Autozone and it throws a P0420 code indicating bad cats. The guy says Toyotas throw this a lot and it could mean other things and I should take it to a dealer.

My only other thought is that it is due for an oil change (last done at 32,200, now at 35,500) and the dirty oil could be effecting emissions. I've never gone more than 3,000 miles before.

Hopefully tomorrow I'll bring it in for a change (yes I can change my own oil, but most places around me charge almost what it would cost me to do it myself) and I'll clear the light and see if it comes on by next weekend when I'll be looking to sell again.


TL;DR: What else can cause a P0420 code besides bad cats? Anyone experienced this>

FWIW: 2004 2.4L Taco with 35,500 miles

 

replace the o2 sensor check out rockauto and get a denso, should run you about 85 bucks. i had alot of issues with my truck and the p0420, if your truck smells like sulfur on start up then you will need a new cat. it seems odd that a sensor would go out at 35,500 miles though mine was great up to 100,000 until i put in my new exhaust. you could try and seafoam it to see if it leaks at all, that could also throw up a code

 

My acura is throwing this code right now too. it is either your cat or an o2 senser. Im not gonna mess with it until I get some other things taken care off. If your nearing your emissions, then I'd worry about it more.

 

ive been reading about the federal emission warranty that is for 2 years and 24,000 miles but it says certain parts are covered for 8 years and 80,000 miles. ive seen it mentioned on the yotatech forums. anyone know more about this and if i will be covered?

i looked up the law and it does cover o2 sensors and cats but idk if thats for the 2 years or 8. it also mentions that accidents can cause your claim to be denied and ive been in 2 but i dont see how they would effect the cats