I have a knocking under the dashboard on the passenger side
does it happen when you do something eg accelerate, turn, try to start . is the CEL on
It could be a heater control servo motor stuck and making a knocking sound, try changing mode controls or just turning the HVAC system off when you hear it and listen for it to stop, it might take a few for everything to shut down on the unit.
Believe it or not, it could be the right front strut.
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