P2187 code
 

P2187 code came up and not sure what to make of it. Upstream O2 sensor reading 0 volts but it was recently replaced so it's not the sensor. Vehicle runs fine, was hesitating for like a week but put some injector cleaner in and it went away, but this code came up yesterday. MAF reads normal and was recently cleaned as well.

Time to carry out some diagnosis with a multimeter.

I would check the connections. I actually pulled the wires out of the connector and hadn't realized it. Had to remove the pins and reattach the wires.