Kiddie pool on the passenger floorboard
 

79 GP.......It's not the Heater core.I noticed it after a hard rain.Most likely culprit(s)?

1. Bad door hinges, allowing the water to come in past the window weatherstrip by the dogleg area. 2.Rust around the top or side of the windshield glass. Take off the reveal molding and have a look. Vinyl top cars are especially bad.

Number 1 is the candidate.And we had a decent monsoon the other day.No vinyl top.

Thanks.

Another thing is to check the windsheild seal. Your summer sun bakes the butyl tape into crispy chunks.

Remove the blower motor .

Reach your hand in a pull out all the rotted leafs and debris that is in the hvac box.

Should be nice and gooey and possibly smelly. Fun stuff.

There is also one small hole on the flat bottom that should be cleared .

You will be able to see with a flashlight looking in.

There is a flap/drain you should be able to feel that gets clogged shut also.

The box fills in heavy rain and dumps into the car threw the lower venting.

I drain some fresh water threw after cleared and soak it with Lysol. Let it air dry and put it back together.