I recently had the car in for a heater core. Over the last week or two, the gear selector has started making a clacking noise when I move it, and feels like something is jammmed in it.
it's intermediate, so I get the feeling whatever it is is moving in there. Any ideas?

 

Take the console off and have a look. There's not a hole lot of moving parts there so it should be obvious. They probably lost one of the tiny gold colored screws in there that holds the HVAC case cover on.

 

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or maybe if the wiring that is in there came loose from the mounting that may have an effect as well. You almost need to stay and watch these guys work on the stuff. I have had some many dumb things happen. Then they look at you with the dear in the headlights look??

 

You would think I'd have learned after taking my sonata in. They spent weeks trying to track down misfires that it turns out never actually existed. Fun stuff. Then refused to do something basic because the battery was moved to the trunk.
I figured since the Monte is newer and bone stock they'd know what to do with it.