P0420

Looked like I am just getting the urd simulator

 

On my 2000 it wasn’t necessary to remove rear 02 sensor, I just followed the wires up into the cab ( under the carpet beside the passenger seat ) you can cut , spice and solder everything in place.

 

Yes I know that... I was just going go to replace the o2 sensor

 

I've seen far worse rust on an O2
Soak the nuts with penetrating oil and cut the shield off with a sawzall. The 12mm nuts will come off even after being rounded off with Vice grip locking pliers. You can do this, the long life of your Tacos engine depends on you. Or buy the sensor and pay a muffler shop.

 

Already tried... so did the muffle shop they said wont be able to take it out.

 

Thar is unbelievable. Considering the shops stock pipe sections with O2 flanges to weld in when necessary.

 

I’ve never seen a nut that size stand up to an oxy / acetylene torch and some vice grips.......it’s the front O2 that sets the fuel ratio, the back O2 sensor just tells if the exhaust is not up to pollution standards.....so just leave it be ???????

 

Bingo

 

Mine was worse. I tried Penetrating oil and vice grips (didnt work). I didnt have access to a torch so I bought a small file and filed the nut edges down so I could get a smaller wrench around it.

 

I bought Denso sensors. 2 rear ones actually because I thought my first one was bad after running 2weeks and CEL came back on with same code. I understand what some of you guys are saying, just putting a band-aid on it. The thing is and I'm sure I'm older than a lot of you guys lol. We didn't have theses sensors back a few years ago and we knew when we had a bad cat or our truck was running like shit. But with 2 new cats and after going back and looking I had actually installed a high flow cat on the rear so that is probably where my bad reading in coming from, and both sensors being new. I believe I can say I should be okay. So how do these guy with headers and high performance exhaust systems get by without these sensors.

 

53 years of tearing engines, transmissions, etc. apart. 30 years with my own shop.... sold my last carburetor vehicle two years ago. Learning all the time on this site.
I think a lot of those performance guys either know these new systems extremely well or they use cheaters like the URD device.

( recently had a family members vehicle throwing the 0420 code, after O2 sensors etc. etc.....turned out it needed a hotter thermostat, that was the end of the code)

 

And who would of thought a thermostat would cause that type of code.

 

And believe me it went on for months and nothing solved the problem......once the hotter thermostat was installed it solved the problem immediately and permanently.........a coincidence ????? Maybe ????

 

Same

 

Anyone knows what the resistance is supposed to be for the rear O2