P2097 code mystery

[gmart07]

I just had a p2097 pop up on the OBD yesterday. I also have a p0301 and a stiff brake pedal when starting the vehicle. Any advice on what it could be or if either of the other 2 problems could be related to to the p2097? I just changed the O2 sensors 2 weeks ago. Any advice is greatly appreciated. This is on a 2011 Expedition XLT with 176,000.

 

[bodabdan]

P2097 is rich on bank 1. P0302 is a misfire on cylinder 2.

My first check would be to look for bad coil or stuck injector on cylinder 2.