Having problems with your 1999 Pontiac Bonneville ?
Leaking into the floorboard of the backseat 1999 Pontiac bonneville sunroof
There are little drain holes on the outer edge of the sunroof assembly. Open fully and look at the right front and left front corners. some of the holes or drains are as small as a .25 inch. Very easy to get small leaf in and clog.
It sounds as though you will have to replace or clean and lubricate the weather strip seal. Take the car to a car wash and vacuum the back floor dry; otherwise it will start to smell.
Repair Help & Product Troubleshooting for 1999 Pontiac Bonneville
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