I didn't get any responses but thought I'd follow-up to my own post with
what I found through my investigation.
I took my 2003 Impreza Outback Sport (still under new car warranty) to
the dealer to have them check the windshield and they could not
replicate any leaks. Only thing they found was a grommet in the
firewall, behind the clutch/brake pedals, that the previous owner had
drilled a hole through to get a wire through for goodness knows what. I
was told by the dealer that they could not replicate the water leak
issue, but would replace the grommet. The dealer also indicated that
the windshield on my used OBS had been replaced so it really wasn't
their responsibility, and asked me to take the car to windshield place
to have them check out the windshield. They did not charge me for any
of the labour on this one.
I took the car to the windshield shop, where they foam/soap tested the
windshield for leaks. I was standing and watching them do this. They
found no leaks in the windshield. So I was left wondering where the
leak could still be coming from. I took the car home and proceeded to
take off the lower dash pieces, and front door plastic in the following
order:
1) A Pillar plastic trim - this exposed wiring for map lights
2) Passenger side lower dash plastic trim, including glovebox - this
exposed the heater core, and flap for the fresh air/recirculate diverter
unit. Easy removal as all plastic is screwed in; no clips are used
except for one on the right hand side of the gray interior plastic to
the far right of the glovebox door.
3) Flip down coin tray - exposed fuse box cover
4) Driver side lower dash plastic trim - this exposed the wiring for
fuses, CRU, optional remote door lock unit, and other wiring. Two
screws at the very bottom required removal, the top part of the gray
plastic is held in by 3 push in clips that carefully pulled allow
disattachment of the plastic. Cruise, and Fog Light buttons carefully
removed by pushing down on plastic clips on the bottom of the button
assemblies. Computer code connector removed by carefully pushing on
plastic clips in the middle of the lower dash plastic trim.
With the amount of rain the last couple days I had the exact conditions
to replicate the problem. With the plastic dash pieces off I was able
to find that water is coming down in through the external fresh air
intake into the heater core. When I turned the heater on I could hear
the water being sloshed around at the speed of the fan. As the air is
being warmed and spread through the vent pipes, the water evaporates,
cools as it travels away from the heater core and procedes to leak down
along the plastic, and wiring from the area where the side window vents
are located. I am taking it in for the 3rd visit in a week to the
dealer with my findings and I'll see what they are going to do.
