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Puddle on my the passenger floor!

Wondering if anyone might know why I have a puddle on my front passenger floor after a heavy rain… it seems to leaking from under the dash

What kind of car is it? And is it a problem that is only associated with rain? IF so, there’s a good chance that you need to clean out the whole area around the fresh air intake just under the windshield. That area is meant to get wet, but is also meant to drain water. If too much gunk accumulates the drains can get clogged up and create enough water so that it flows in where your fresh air comes in. If you let it go long enough you’ll likely wreck your blower motor and/or its electrical connections. Pop the hood and look up near the bottom of the windshield - lots of gunk? Clean it out.

I’m just speaking from direct experience there. There are other possibilities like actual leaks in the body. So if there is no reason to believe that you’re “flooding” your fresh air intake, I’d visit a body shop.

its a 97 Buick Century Custom , you probably hit the nail right on the head, oh and that would explain why I had to replace the blower motor and resistor switch, I’ve only been driving the car for a few months , my little brother drove it for a few years , and I have a number of things to fix on it that have been neglected, but thanks for the suggestion

You’ll also want to check the drain tube for the ventilation system to make sure it’s open. The tube will be on the firewall, low on the passenger side.

so I tested both the openings near the windshield by pouring water in there and both openings drain right along the firewall , and down and out through the bottom of the door jams and there’s a small groove going right down to the rocker panel area where the water drains out … soo now I’m even more confused

In addition to the drain from the fresh air intake, you have one or two more drains in that area.  The A/C (which also runs in the winter when you turn on the defrost) drains down there, but usually on the passenger side and if you have a sunroof it has four drains, including one that often leaks in the area you are talking about.  

To check a sunroof drain put the car in a dry area and pour water into the gutter of the sunroof so it flows to the corner near where you may have a leak.  The drains sometimes get clogged and leak into the car.

pull the passenger side windshield wiper up and pour the water on the windshield at about the center of the passenger seat as you look through the window. There is a rubber gasket at the bottom of the windshield there; above the fresh air intake. If the gasket is loose, water will pour into the fresh air intake, throught the cabin air filter, and into the blower motor. Alternatively, you could pull the passenger side wpier blade off and remove the facia at the bottom of the windshield. DO NOT PUT A PRY BAR ON THE FACIA. That will break the windshield. YOu will see the rubber gaset - just like the door window gaset - on the bottom of the windwhield. If it isn’t seater properly, reseat it (push it up).