2003 Malibu Interior Leaks

I have a 2003 Malibu that over the last year has developed a slight leak on the passenger side floor mat. Nothing major just a small damp spot when the car sits outside and there is heavy rain. Yesterday, I went to start my car after a real heavy rain and the remote key fob would not open the doors/trunk. I keyed in and the interior lights were out. Both winter floor mats (Driver & Passenger Side) had large amounts of rain water on them. The car started right up but shut off when it was idling down.

I went outside a couple of hours later and the key fob still would not work. The power mirrors and power windows now worked. Also the digital clock was on but the radio would not turn on. Still no remote/interior trunk release nor power door locks. I tried to start the car a couple of more times. Once again it started but would shutoff when it was idling down. Looked under the hood at the fuse box and checked the two inside. Nothing looked wet. Looked at some of the fuses and they appeared ok.

The car was towed to Chevy dealer. An hour or so later the dealer said the drivers side fuse block was corroded and that would need to be replaced. They had also never heard of a Malibu interior leaking and had no clue where the water was coming in from. I assume the water has to be coming in from the top of the window near the two roof rails. Has anyone else had this problem?

Their is a drain hose for the heater core and condenser for the air conditioning. On a hot with the air conditioning on it should drip. Put the car on jack stands and look under the heater core. Its about 5/8 inch diameter hose. Use a coat hanger or something else to clean out this hose. The hose is about 4 inches long. Close to the bottom of the fire wall.

Thanks for the information. I'll take a look at the drain hose.

According to the dealership, the leak was traced back to the roof seam near the plastic door rail. Water was entering the seam and going down the front window pilliar. They needed to remove the interior linear and plastic pieces in order to see water entry point.

I had the same problem but mine was a cap at the bottom of the windsheild trim.
It separated and allowed rainwater to leech into the floor pans.

I bought a tube of windsheild sealant, caulked the bottom area of the trim seam and snapped the cap back on. I haven't had any water leaks since.