HELP having issues on bank 2 lean
 

had a p300 missfire then a 302 which is cilinder 2 i replaced de coil and problem solved (not quite) currently i went to retune my car with ecutek. the tuner said the bank 2 was leaner he was giving the same % of gas and the bank 2 didn't responded stayed on 13.5 and the bank 1 was on 11.8.

He then loaded a map for turbo with the speed density to see if the mafs where the problem. Nope still bank 2 lean, then he said check your o2 sensors they are reading different voltage even 1 volt difference which he pulled other 370z logs and the o2 where slightly parallel to one another. i am planning on changing again my o2 sensors. He tuned individually bank 2 making it richer to maybe even the odds until i change my o2 sensors and try again.

My question is: is there something else causing this? voltage and the bank 2 be leanner other than the o2 sensor, don't want to think it is an injector problem in cruise he performs great, even thou my mpg are 13.8 which before was 15.4. Maybe a vacuum leak? but for now i am :owned: and if this keeps up maybe sell the car.

Somewhat of a common issue - there is likely a hairline crack on one of your cats. I’ve seen the cracks hidden behind the cat heat shield.

i don't have cats

I see you have stillen CAI. I would check all the clamps on bank 2 just to make sure you have no metered air going in. Also since your exhaust is custom, I would definitely check for leaks there as well before you start throwing parts on it.

If he ran speed density and still had the same issue, the CAI wouldn’t matter since speed density is based off manifold pressure. I would look at exhaust manifold leaks or check the gaskets where the test pipes meet the manifolds. You could also try swapping A/F sensors. Also there may be a light misfire condition or an injector issue.

will do that i'll swapp sensors to see if the problem shifts to bank 1 or stays the same.:stirthepot:

I believe there's a fused heater in one of the O2 sensors. I think it's the post Cat one. They have been known to blow and it's a cheap/easy fix if it's just the fuse.

where is it?

Did you get to the bottom of this? What was the issue?