I am showing the following codes:

P0161 - o2s Heater Circuit, Bank2 - Sensor 2, malfunction

P0420 - catalyst system, bank1, efficiency below

P1416 - Air system, bank2


What could cause all these codes to come up at the same time?

 

bank 2 sensor 2 is the rear o2 sensor....

looks like your cats are bad

the air pump could be bad and not getting things heated up properly.

 

But why would Bank 2 O2 be bad, and bank1 Cat be bad?

I dont see how its not getting enought heat...there is alot of heat comming from under there.

 

see if these help....

code 0161
code 0420
code 1416

a quick run through to me looks like your sensors may be bad, which is tripping multiple codes all correlating to one problem.

 

O2 sensors? all 4?

also, what do i do when i want to run headers with no cats? how do i make it so i wont throw a code every 5 minutes?

 

O2 sims or have someone with PCM software (HPTuners, EFILive, LS1Edit) delete the rear O2's.

As for the problem solving...clear the codes and switch the rear O2's to see if the problem follows the sensor. At first glance, the one code would tell me the B2S2 sensor is bad. The other would suggest your driver's side cat is starting to go. But, I'd try a little troubleshooting before I threw parts at it.


**EDIT FYI**
B1S2/B2S2 part #25312197
B1S1 part #25312197
B2S1 part #25312196

 

I think it is b202 going bad. but as i said, over winter, LT's with no cats or rear o2s, so i am not going ot bother with parts now.