I have done some web searching and haven't found much. So, I am turning to those who know most about Monteros. I have a rain water leak that is coming in at the lower "A" pillar at a gap in the sheet metal panels on the pinch weld behind the push on body weather strip about two inches up from the bottom of the dash.
I'll tell you what I have done so far. I pulled the front fender and cowl, removed all the sealant from the cowl, primed, sealed, and top-coated. While the fender and cowl were off I used a syringe and water to try to duplicate the leak, none found. Installed the fender and cowl and used the syringe again at varying levels to try to find the leak, still nothing. I have used a garden hose and soaked the thing from top to bottom STILL no leak! However, even if there is a heavy "dew" or light rain I have water getting in. When it is raining, and no tornados around <img src="/forums/images/graemlins/scared.gif" alt="" />, I can open the door and pull the seal and see the water dripping from the point I described. It is not coolant just pure water. All this happens with the truck sitting still. I have pulled the "A" pillar trim and cannot locate anything. I have checked any grommets and found no leak! I pulled the trim around the outside of the windshield and cannot find a spot that leaks!

So! Anybody have any ideas? I feel like I have exhausted every avenue and hope someone can recommend something to try!

Thanks!

Are you sure it's not the heater core? worth a look...

Have you cleaned the drains for the air inlet area? Slanted rubber tubes coming out of the firewall with a cross cut in them. Drivers side or passenger side leak?

Dang! Thought I covered it all! Drivers side.

Where are the tubes you mentioned? Engine compartment?

Goes from the inside firewall to the heater core in the passenger compartment. There will be 2 metal tubes going through the firewall which will have rubber hoses connecting them to the core.

One other thing is it could also be your windshield mating surfaces in that same area. This happened on my Gen I. There was rust and it had gotten bad enough that the rubber seal no longer worked to keep the water out because the rust particles effectively pushed the seal away from the metal surface and created a big enough gap that water would seep in when driving (wind pushed the water up to the seal) but not when pouring water on it when it wasn't moving. <img src="/forums/images/graemlins/frown.gif" alt="" />

I think they go to the air plenum under the cowl. The plenum has a curbed inlet into the hvac ducting to avoid water ingestion. The drains are in the low point of the plenum to keep the plenum from flooding over the curb in a frog strangler. They get clogged from the crud that gets into the plenum past the grate.

I have a 96 and my windshield is glue in but I did look for rust perforation. My first thought was to look there.

I will look further for the drains you mentioned. My plenum, under the cowl panel, drains behind the fender via a "trough" below the area where the wiper transmissions mount.

I have thought about buying one of those small inspection cameras and poking around with it or pulling the entire dash and see if there is anything to see...

The truly weird thing about this leak is it seems to be a hole straight to the open sky! It lets water in when there is a heavy dew even. No driving at all required! Yet I still cannot get it to leak with any other source of water. I'm pulling my hair out! I tried a dye in hopes of using a black light to find the source but cannot get it to leak other than "natural" sources! GRRRRRR....

Smoke test? Pressurize the interior with something like a shop vac, blocking the rear air exits and the hvac intake...

Cool!

This most certainly is not it, wrong model, doesn't quite fit description, but here is my experience anyway:

My gen 1 had a mystery leak that baffled me for some time. Finally in frustration I took the whole dash out (not a simple process, for me at least). I discovered that the junction between the front firewall chassis cutouts for the outside air vents and the hose for the outside air vents was leaking. The rubber gasket that mated the 2 surfaces was dried out and not completely sealing. Water was running down various harness snakes and not following a straight path down to the floor. I still don't understand why water was there in the first place (must be a drain line somewhere) but sealing the junction with silicone fixed it.

Smoke testing would work if I could find a source of smoke that didn't make it smell like a rib factory or an ashtray for the next two years! LOL!

I thought it might be a grommet somewhere and checked them when the fender was off.