Problem of loose door panel clips--3 contributing factors
1) PO removed vapor barrier and then did not replace it on the inner door frame
2) then--when car is in rain--water will go down side glass inside door and will wet the pressed paper door panel backing and break it down
3) or--use of hose stream on side of car will do same panel damage--and puddle inside door bottom as well--a bad place to get rust started.
BTW--never take a Coupe through a car wash!!
The cure--if backing is not too damaged: brush or spray the entire backside of the door panel with clear POR-15 or other impervious type moisture barrier coating--this will provide an absolute barrier and preserve the original door panel backing. Of course avoiding #2,3 & BTW will be a big help as well.
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