P0420, P0156, P0158

Has anyone got these P0420, P0156, P0158 codes and it was a dirty throttle body or MAF causing the codes to go off almost every other short drive to the store and back?

 

I’d suspect an issue with the oxygen sensor before I would the MAF or Throttle Body.

I would take a look at the O2 sensor voltage (B2S2) at idle.

 

This is one of the downstream sensors that I put a plug ant-fouler on since i removed my CATs. I Was generally getting a P0420 or P0430 every 3 or 400 miles but now its just about every time make a short trip down to store and back.
So something has changed, I think i also remember finding that this O2 sensor had a dent on it near where the wiring comes out of the shell. However its been like that for months and now CEL is going off all the time.
Or could it maybe be the steel wool i put inside the anti-fouler is burned up and now causing computer to throw a code more often ?

 

P0158 is for abnormally high voltage while in Active Air Management.
Basically the truck (ECM) is commanding the tuck lean, and the O2 is reporting a rich condition.
Live data would be a good place to start.

I am not saying your truck is running reach or lean.
So don’t get that confused here.

 

It might make sense if the truck was actually lean because i have a spectre accordian intake tube that is supply ram air to make cold intake box.
Wait P0158 is high O2 voltage bank 2 sensor 2, so when the voltage is high that would or should mean that the mixture is rich?
But this would be a downstream O2 sensor i thought only the upstream ones were Air fuel ratio O2 snesors

 

The are, P0158 is for the downstream sensors.
The ECM forces the truck Rich and Lean, then “calculate” the condition of the converts based on the O2 readings. The rich/lean is intensional.

If you had a real lean condition, you’d have a code for the A/F sensor. (Upstream)