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The cowl area just below the wipers has tubs on each side of the car that collects water where it will stay until it evaporates.

Is this supposed to happen? Or do I have plugged drain holes?

Is there any work around for this?
 

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There should be drain holes in that area. Search around until you find the small slots that drain water. I'm betting they're plugged up with gunk. When you find drain hole use a small rod like a metal clothes hanger, that's been straightened out, to "rod out" the passage.
 

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'70 Esprit TA clone Pontiac 400
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There's no slot or drain in the cowl air plenum from the factory. If the car is driven it rolls and sloshes around and most rolls out the sides and drains out the bottom. If the car sits outside or is washed and put in a garage routinely the water will rust a hole above the brake pedal first because the pond that forms is deeper on that side and takes longer to evaporate.

The "work around" is to fill the area that ponds with something like fiberglass resin so the water can't form a pond.

On top. I hate to think how much trash has gotten thru that plastic grill and is on the inside. How hard is that to clean?
Use a shop vacuum with a nozzle taped on the hose and keep sticking it down the side. Pull it up and pull the leaves and debris off the nozzle. Repeat till you don't get junk stuck on it. Then use a stiff wire down the side to break up sediment that's cemented together and repeat the vacuuming process.
 

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'70 Esprit TA clone Pontiac 400
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That's crazy if GM didn't provide a drain hole and a tube for water to run.
If the car is driven most of the water rolls out and the remainder evaporates. It is really only a problem if the car routinely sits wet or gets parked for extended periods wet. . The depression above the brake pedal provides clearance for the reciprocating transmission for the windshield wipers so you have to be careful not to fill it till there's interference. On the other side, the little pond that can form a few inches to the right of the passenger windshield wiper mount only does so if the car is parked sideways on a hill with the passenger side lower, rarely is that one rusted through. But no fear, a leaking heater core sometime during the cars life usually rusted the passenger foot well and toe board anyway. Between cowl rust through on the drivers side and core leaks on the passengers front floor repairs are needed very often on 2nd gens.

I've seen the cowl rust through even on cars that were babied and never driven in rain or snow. This happens if the car gets washed and parked inside. Without moving the puddle just sits there and in a garage there's little air movement to evaporate the pond. It may take weeks , a month, or longer in cold weather up north for the water to finally evaporate. Same kind of thing happens in the rear window channels and trunk hinge area.
 

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When I finally get around to restoring my 76 trans am, I will make drainage tubes and put drain holes in the cowl. My car will only be driven occasionally.
 

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Just park on a slope or drive around the block to air dry. Good intentions may just be giving rust somewhere to start. Make sure it's all clean inside your cowl, hot soapy water with a degreaser and get rid of built up gunk and silt in the crevices. Be aware that the cowl sides drain behind tne kick panels so sticking a hose in there will often result in filling the cabin too. Many have added a larger lip or even a round container cut in half and attached it to the kick panel opening top so that excess water drains around the cabin opening.
 

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Might do like the 3rd gens, they have a tube that runs from the cowl. It runs through the car and is behind the kick panels. Water gets into the cowl, runs out from drain hole, through tube and out of rocker bottom.
 
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