On my 2000, the fresh air intake in front of the windshield had the holes mostly blocked by plastic. I don't know if it was intentional for the molding to do that, but it restricted the flow of fresh air from outside to the vent system. Instead, it would pull warmer air from the engine bay.

What I did was to take a drill (using a bit slightly smaller in diameter than the width of the squares) and pop out the thin plastic in each of the holes. This worked remarkably so that the air flow from the vents was the same temperature as the outside air. 57F outside air, 59F coming from the vents. 75F outside, 77F coming from the vents. It was consistently 2 degrees F warmer on the inside, but it was not a detectable difference by my hand, only be thermocouple.

HOWEVER, I have no idea what will happen when it first rains, or when it snows, etc.

TimR

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