so i scanned my evo for codes and i got a p0172 code meaning in running too rich, ive done a boost leak test twice just to make sure and i cant find any leaks.... so it cant be from a boost leak anyone know why?

 

I've got the same problem, and couldn't find much on that code on this site (besides check for boost-leaks).
Also I noticed sometimes it goes out by itself, then a week later comes back.
Did you upgrade injectors? Mine started coming on after injectors and tune.
I think it may be a vacuum leak, or something in the tune. but I don't know.
I've seen it come on while my car is idle-ing at a stop light.

if you figure it out, please report back on how you fixed it.

 

It means either LFT mid or LFT low (long term fuel trim) is pegged at 12.5/-12.5.

This means your fueling is far enough from 14.7:1 at idle or cruise to max out the fuel trims. Ideally the should be under 5%.

 

Check your front O2 sensor.

 

Thanks, I will start to log those values.
I noticed that when coming to a stop after driving, the wideband goes into the 11's at idle for about 10 seconds while slowly climbing to 14.7. (car is warmed up already)

How to adjust the fuel trims, in which table?

 

Well in my case it my rear o2 sensor. And that caused a check engine light. So check everything.

 

The rear O2 has no effect on afr, it is there to measure cat efficiency.
If you get a CEL caused by the rear O2 it shouldn't affect your car.