Has anyone dealt with P2188 (rich condition at idle in Bank 1)

I searched and saw some stuff saying Mafs worked for some. I tried that to no avail. I then smoke tested and found that I had no leaks either. I am thinking it must be fuel related at this point.

I never had this code until I changed fluids and all filters. I went to k&N stile filter and was thinking that it could possible be flowing too much air. That however does not line up as I only get the code on one bank.

I am thinking I am going to run some fuel injector cleaner (Techron or similar) and see if that helps anything. Any advice is appreciated.

 

Appreciate the advice. I switched MAFs and even bought a new one, with no change. That was the first thing I tried and was hoping for an easy fix. Not sure what else I could try and switch. I looked at the voltages of both pre cat 02 sensors and the voltage readings are the same, so I don't think the issue is there either.