I installed my JWT ecu and after punching it a few times i get a check engine light which reads P0174 SYSTEM TOO LEAN BANK 2. Can anyone shed some light on this issue?

 

Ecu is no good send it to me LOL...

 

Can you verify that it's the JWT ECU? Put your stock one back in and test to be sure. If it's the JWT, you have to send it to be reflashed.

 

You need a wideband to verify when it goes lean. Chances are that its just lean when you let off the gas after a WOT run. You can't trust the factory O2s that much.

 

My stock ecu used to throw a bad rear 02 sensor before

 

I agree with essential. JWT rarely messes up an ECU flash so most likely it is your 02 sensors giving a false code. If your going to start doing upgrades such as that then you need a good way to measure the vitals especially AFR. AEM has a good one but it ain't cheap. Dont get a cheap auto parts store AFR gauge as hose do essentially nothing. Lambda or bust

 

jwt n/a ecus are known to run a bit lean, but i would not put any stock into what a factory o2 sensor is telling you.

get a wideband if you are worried.

 

its not the jwt, trust.

 

Bad O2 sensor!

 

14.0 and slightly above