I recently replaced my heater core. After I finished I found this thing laying on the floor board. My AC no longer blows cold air on the passenger side. Could this be related and if not I really would appreciate some pointers on this.

 

Could be the gear that links the vent door to its controller motor. Background: The climate control system uses 5(?) motor controlled doors to control airflow across the heater core, the AC evaporator and to feed air to the vents/floor/dash. Given you have cold or hot not going to one particular place, I'd suspect that the motor/gear to the door rod came apart. If you don't have a blinking AC/REC light, the computer didn't throw a fault which suggests the motor is ok but its disconnected from the door.

 

Thank you for the feedback. I'm still looking but no signs of an empty port.

 

I believe the ashtray has some gears that look like that.