Cel help!!!

Posted this on TTORA as well. Hope to get as much input from y'alls on this as possible.

Truck is a 2001 Taco Prerunner V6 auto with 157K.

Wayyyyy back when, it threw a P0420. Kept going on/off because I kept removing the neg wire to set turn it off.

Then, being a cheap-ass, thought the O2 sims would help so I bought a URD O2 sensor sim. Installed that and ran OK for about 400 miles then a P0136 came up. Now, without the sensor sim and running as stock, I'm constantly getting the P0136, kept resetting the CEL by removing the neg wire on battery. Strangely, for the last 800 miles, ran CEL free.

Could it be that I fucked up the wiring when installing/uninstalling the URD O2 sim?

OR

Could it just be a bad sensor?

OR

Could it be a bad CAT?

*note* my exhaust smells disgusting, like my bike because bikes don't got no sensors.

thanks y'alls.

 

Cat could be plugged for sure, especially if your getting a heavy odor out the exhaust. Yota's dont like other sensors but oems in my opinion...but some would argue.

 

Exhaust smells like rotten eggs or worse ?? Sounds like a bad Catalytic (or 2)...

 

well, i don't have the sim on anymore, not for about 1K miles.

i understand that it can be a bad CAT or the sensor itself, tryin' to work something out with Steve (Gadget) from URD.

any other suggestions???

 

alrighty, i'll try testing out both theories.

but how the hell am i supposed to test the exhaust for leaks?

any clever ideas of how to test it out other than the waiting for a cold day to see where it may potentially be leaking from?