Cel 2097

I've had my LGT for a while now and I have recently found it to be pulling a CEL for code 2097 which means one of the banks are running rich or something to that effect. I generally reset it by pulling the ECU fuse under the hood then it goes away. I thought it might have been a fluke the first time but it seems to consistently come back. I have also noticed that it has only come on since the weather has gotten cold. Below freezing temperatures.

Any thoughts on what I should look at? I am out of warrantee and I don't think this is covered under the powertrain warranty.

I generally reset it by pulling the ECU fuse under the hood then it goes away.

^I don't think this is a great idea..

Otherwise there is a sticky here with all the codes. Find it, call the dealership, ask what needs done, do it yourself if possible..