p0156 o2sensor mil/vsc lights on

[ilroute66]

I have changed bank 2 sensor 2 o2 sensor the mil has come back on after being reset. Please help! OBD2 reader gives 2 codes, both p0156. passenger side downstream sensor behind cat was changed. any ideas

thanks from route 66

[jetwhine]

ilroute66,

I would try changing the bank 2 sensor 1 and see if that fixes the problem. 2 codes of p0156 does not make any sense. It sounds like the comp. does sense something wrong in the bank 2 system. I would try one more sensor.

[ilroute66]

Originally Posted by jetwhine

ilroute66,

I would try changing the bank 2 sensor 1 and see if that fixes the problem. 2 codes of p0156 does not make any sense. It sounds like the comp. does sense something wrong in the bank 2 system. I would try one more sensor.

that was my next idea and then having the cat changed out?

the 2 codes are both generic p0156 but when I convert to toyota type auto it switches to one code of p0156? new reader just getting the hang of it.

thanks i'll try the other sensor next .

[jetwhine]

ilroute66.

I can't amagine that the cat would be bad. I have an 03 and have not had any issues with a bad cat. I would think that it you had a bad cat, there would be more problems than just an o2 sensor.

[outsider60]

Originally Posted by ilroute66

I have changed bank 2 sensor 2 o2 sensor the mil has come back on after being reset. Please help! OBD2 reader gives 2 codes, both p0156. passenger side downstream sensor behind cat was changed. any ideas

thanks from route 66

First thing. is it a v6 or v8
makes a diff on the bank1 or bank2.
Also, if you had a bad cats. a code p0420 or p0430 would be present.

[tdewitt34]

i HAVE THE SAME THING BUT IT COMES FROM A MALFUNCTIONING REAR O2 JUST CHANGE THE SENSOR AND YOU SHOULD BE OKAY. ALSO IF YOU HAVE A 420 OR 430 CODE FIRST TAKE IT TO GET EMISSION TESTING EVEN THOUGH THAT CODE IS FOR "BAD CATS" A TEST WILL TELL IF YOU IF YOU REALLY NEED THEM. i HAd THOSE CODES TOO. i DIDNT BUY CATS i JUST PUT SOME HOME MADE SPACERS IN AND THE CODES WENT AWAY. I THINK THE ECM DOES NOT READ THE SIGNALS AFTER A WHILE AND TOYOTA WANT YOU TO BUY A EXPENSIVE PART AND REPPROGRAM YOUR ECM TOO! sORRY FOR THE LONG WINDED ADVICE BUT i HOPE THIS HELPS IN SOME WAY

[ohiois350]

I just have the dealer checked today and the code P0156, bank2 sensior 2, how hard is it to install? and where is it locate?