Occasional water leak on pax side

seem to have a tiny leak that happens sometimes when it rains…any ideas? It has to be from the general pax windshield/ firewall area.

 

From what I've seen here; If you pull your cowl under the windshield you might find your area of intrusion, rust in the corners. High probability around the windshield as well.

 

Does it do that with the heater on when it's not raining?

 

@alb1k nailed it.

This leak is covered in the stickied Definitive Leak Thread: https://www.tundras.com/threads/definitive-2000-2006-cab-area-rain-water-leak-thread.70464/
There's even a video showing what causes the leak and why.

Be prepared to buy a few extra cowl fasteners, both the receiver and the plastic pieces, you're bound to break a few popping the cowl cover free.

 

Well, to be fair, I did learn it from you.

 

I will watch and learn! Thanks guys!

 

The little nylon nutserts on the cowl have a gasket that deteriorates and allows water in

 

This the issue? Or underneath the cowl out of immediate sight?

 

Again, watch the video in the link I posted above. It should be super clear. Click the link, skip straight to the video. Watch it, then scroll back to the "Cowl fasteners (all models)" section of that post to get part numbers and other details you'll need to know to fix it.

What you need to get to is under just the black cowl cover panel in your pic which is really fun to pop off, because you can break the tophat-shaped receiver in the body, or the black plastic snap in the cowl cover. There are a few ways to fix it, either replacing the part, or using auto-paint-safe sealant and sealing it in place. You'll see exactly which fastener is a problem in that video.