Water in floor board - 98 GTP

[GTowner2016]

My brother in law has a 98 gtp. There seems to be an issue with water in the floor board. He checked and the heater hose was dry rotted so he replaced it thinking that was the problem. It still does it. We are stumped as to what the issue is. I had a SE for a little over a year and it done this during winter but only when it rained, and I found that the weatherstrip deal under the plastic below the outer windshield, that redirects water from the ac opening, was falling and letting water in that way. But his is doing this all the time. What could it be?

Also, his coolant light isn't going off and it is full of coolant. Any ideas here?

[SubwayGuy]

Windshield cowl is leaking. There's multiple discussions on this, and some threads on fixing the issue.

[GTowner2016]

Thanks I'll look those up!

[SubwayGuy]

Thanks I'll look those up!

Easiest way to fix it is to caulk the cowl to the windshield. Only on the passenger side though.

[SubwayGuy]

http://www.grandprixforums.net/threa...-Permanent-Fix

[primem]

+1
I didn't buy the new part
I put weatherstrip adhesive on the factory seal to keep it from falling off, then rtv on the passenger side of the cowl to the glass. then rtv on the roof cellular antenna.

[GTowner2016]

So it will leak even if it isn't raining? My SE only done it when it was raining outside.

[Scottydoggs]

is it wet all the time? or just after it rains?

all the time its the heater core leaking.

[GTowner2016]

Its all the time. He said the heater core was checked and it didn't seem to be leaking. I checked the windshield cowl myself and his was fine. Not sure what this could be

[Scottydoggs]

if its wet now the only 3 things it could be is the a/c drip tray drain, the heater core, or the cowl.

keep in mind the foam under the rug is thick and will hold water for a long time and stink like hell if you dont dry it up.

if you cant tell where its coming from you need to take the rug out, and watch for the leak to happen, hose test, run the engine see if the core leaks, turn the ac on, se if its leaking then.

[GTowner2016]

The A/C doesn't work. Need a compressor. So it would probably HAVE to be the heater core, right?

[Scottydoggs]

unless its still soaking wet from the cowl leaking?

take the foot cover off, the door sill trim and the side plastic. pull the carpet back and see if its leaking, just run a hose over the windshield and wait to see the trail of water.

you also should be able to see coolant leaking from the middle hump under the dash if its the core. coolant smells sweet, and has a slick feel to it.

[GTowner2016]

Thanks, I'll check it out when he gets back home. He isn't very car knowledgeable so I have to see myself.

[Reptile]

I just replaced the heater core in mine....have fun with that. LOL
You can take a flashlight, and look up under the dash between the console and firewall to see if there's any coolant dripping down. If you see green or orange...or whatever color your coolant is, that's the problem. It's about a 3 hour tour from start to finish.

[GTowner2016]

Well on the bright side, it's his car for him to deal with, not mine. But on the other hand, I'm having to do a complete engine swap along with putting upper intake gasket on new(er) motor as well, so maybe I should envy the 3 hour job he has.

[ExLimey]

I'd put my money on it being the cowl. It's about a $10 part to fix it and 30 minutes if you're slow. If it were the heater core, I'd think you could smell it. Doesn't dexcool have a distinct smell? The coolant level in the radiator/overflow tank would be going down as well.

[GTowner2016]

He had water in it, not coolant (he's an idiot). So you wouldn't smell it. He did recently put coolant in it and the upper radiator hose seems to be condensating on the top of the hose, and there is coolant leaking from somewhere that looks like straight down from motor. Very lost on this one.