1994 Pontiac Grand Am Q&A
1994 Pontiac Grand Am Question: How to stop water from leaking in behind firewall into passenger compartment?
This began years ago, and has taken me nearly 3 years to determine where the leak is coming in. Car has been sitting since 2009, and needs to be sealed. Apparently there is a great possibility that it is a manufacturer defect in behind the vents outside, beneath the windshield, but GM claims this leaking, running down behind the gas and brake pedals and pooling on the floorboards on both sides of the vehicle is due to car owners leaving the windows down when it rains. In otherwords, GM refuses to acknowledge the likely defect and cause of the leaking problem at all. Would hate to have th junk this great car. Never had any major problems with it otherwise ever. Hope someone can help. Thanks. - SPDworks
it is probable heater core if you lived in northern states you would know by steam on windsheld when you use your defroster - 1lostcause