So i got the infamous PO420 code... so i need an O2 sensor... so i got one from URD.... So tonight I go to replace it and to start I soak it down with PB Blaster and ass the rust disolved.... I saw what came to be the highlight of my night.... 2 very rounded over nuts... after having a fit and throwing tools i calmed down and then just started to get angry some more.... the stupid carlot where i got my car tried to replace the sensor and failed... they knew the sensor was bad cause the light went off less that 2 miles from the lot on the way home... so i went back and they gave me the stupid "no warrenty" line....
thank God i have access to any tool I need so tomorrw im going to use a nut extractor and get the stupid things off... then clean up the threads and use some nice stainless nuts with plenty of anti-sieze....

sorry for my venting but Im alittle hot right now....

if anyone can help me with the thread sizes it wouidl be great... i think the nuts used to be 12mm but im not sure... cause the 10mm spins over the nut.... hopefully i dont break a stud or i will flip ˟˟˟˟˟.... so if anyone knows the thread it woudl be great...

thanks guys

 

http://www.4runners.org/articles/02sensor

 

thanks... do you know the thread size? 1.25?

 

You might need to call the dealer on that one.
It is either a 1.0 (coarse) or 1.25 (fine).

 

anybody? what size nuts shoudl i buy?

 

Just go to the dealer and tell them that you need a nut for the O2 sensor bolt/stud and they will be able to give you the correct replacement part. That's what I did when I replaced mine. I think it cost me 80 cents apiece.

George

 

Don't mean to highjack. Does anyone know how the studs are attached to the front exhaust pipe? I may have to cut the studs out because the nuts are too rounded from rust to remove. If I do cut them out, I'm wondering if a bolt can be fished from the bottom up.

Troy

 

Worst case scenario - any reputable exhaust shop should be able to weld a new O2 sensor bung on the exhaust system.

 

Wait...I thought the P0420 was the catalyctic converter in Bank 1. I got that code today, I have been in an ongoing battle with my cat. for over a month now, you can go here to read about it: https://www.yotatech.com/forums/f2/dual-cat-converter-4runners-67521/

Anyway, I thought that it just meant that the cat. wasn't performing to spec...thats what the little reader the dealer had today said.

Hmm...

Fink

 

it could mean the cat is bad, or the O2 sensor is bad and is then telling the ECU that it thinks the cat is bad when it is not really.....

i put the new O2 sensor in and so far no codes.... we'll see

 

Cool, let us know how it goes...it usually takes about a half tank to a full tank of gas for it to throw it, so, let us know!

Fink

 

im hoping soooo much that i dont throw a code.... i cant afford a new cat right now... i want to buy a lift!!! and if i need a cat... the lift will have to wait