Im getting a system too lean code for both 02s. Been doing it for a while. I can clear the code and it comes back eventually.. What would cause this? Bad 02s?

 

Hook a scanner up and see if the OS2s are switching around like they should. If they are then you're really burning lean!

 

Im having the same issues its been doin it since I installed my turbo kit. Im goin to change my o2s this weekend to see if it stops or if its tuning issues.

 

Most likely a tuning issue and you need more fuel during closed loop operations.

 

Low fuel pressure, vacuum leak, exhaust leak, MAF sensor failure. Those are the first things that I think about when both banks are reading lean. Also, is this a new setup, or an existing setup that has been working just fine until now?

 

I have been running the truck on the current setup for about two years with no issues. I changes the injectors to 72lbrs and it has been throwing a code since the retune. So Im sure its tuning related but wasnt sure. I am waiting on my new wideband to get here and will be logging through hp for nelson to adjust the tune.