25th Aug 2001, 20:44

Sounds like your A/C drain line (on the bottom of your engine somewhere) is clogged by dirt or mud. When this happens, the condensation which would usually run out onto the ground backs up and fills your floorboards. If you locate the drain line and clean it out (try a coat-hanger) that should fix your problem. Good luck. Dave.

11th Jul 2002, 07:33

I have a 1998 Grand Cherokee Limited, and it also has moldy wet floor mats on the passenger side--front and rear. This just started recently. The Jeep dealer said it was due to clogged AC drain from tree leaves. They blew out the system with compressed air--but the problem quickly returned. Any suggestions?? Thanks!

29th Jul 2002, 10:33

I have a 1997 grand Cherokee Laredo. The AC condensation is draining on the inside resulting in extremely wet carpet. Unable to locate the outside drainage hose and the dealer wanted. $710.00 to repair.

30th Jul 2002, 12:17

Regarding A/C Condensation-

I just went through this with my 1997 Grand Cherokee. The first thing I looked for was the condensate drain line. I could not find it and, at my wife's suggestion, took it to our local mechanic. He was not able to find it either and suggested I take it to the dealer. (Not at $80.00/Hour!!)

I decided to try to look again. I found what appeared to be the drain on the inside of the vehicle. It's located under the dash on the passenger side. The problem is that it is part of the whole Condenser/Fan/Vent assembly and it spans the whole passenger side. The drain drops down from this assembly in a "V" shape to a round (about 2.5" Dia.) piece that goes through the firewall. (This will make more sense when you see it.) The other side is not visible because it is behind a boxed portion of the body.

At this point I realized that removing the whole unit was going to be a huge task that I was not ready to do. Also, this would probably not be the last time I had to do this.


I decided to drill a 3/8" hole in the middle of the round piece that fits through the firewall. (Have a towel that you don't mind getting dirty ready). I then used a coat hanger to clean out as much of the leaves and other black gunk that had accumulated as possible. Running the A/C while you do this can help, but it will also make more water.

Once I felt I had most of the garbage cleaned out. I blew compressed air into the hole. I then let the area dry out. I used a 3/8" NPT Pipe plug ($1.00 at the local hardware store) and some black silicone sealant to plug the hole.

I've spent the past week with a wonderfully dry interior despite the high temps and humidity we've been having. Even better, if and when this happens again, I now can easily access the drain.

Hope this Helps!

13th Nov 2002, 05:26

Hello from St.Petersburg, Russia. While owning Grand Cherokee 94 experienced the same problem with flooding under passenger floor mat. It mostly happened after hot days long rides with A/C on and when I applied servicemen they stated the reason was clogged A/C drainage system that is widespread Grands failure. Tried to clean the duct exit on the lower bottom beam firstly, then drilled a hole from passenger feet side and cleansed the duct with the wire, but no positive outcome reached. The remedy is to dismount dashboard and reach the upper drainage duct opening that costs 300 USD here. Generally the car became a headache upon mileage 110 K.

Best Regards, Arthur Gavluck.

12th Jan 2003, 10:18

I had a 95 Grand Cherokee before my 98, and it had the wet floorboard problem on the passenger side. I had several mechanics look at it and they all decided that the heater coil was broken and needed to be replaced. Since the part is extremely hard to get to (under the dash) and requires taking out the dash and electronics and... I don't even want to get into it... I traded it in for a newer model with 4wheel drive.

7th Aug 2003, 20:39

I have a 93' with a leaky passenger floorboard. I tried to clean the drain with an huge 3/8" drill bit. I drilled all the way through the firewall and I patched over the remaining hole. (No trash or dirt came out of when I pulled the bit back out either.) Still leaking. Man is it hard to get to or what?! I can't get a new one until January and this heat is Florida is a insane. I wish I had some diagrams to look at.

24th Aug 2003, 23:21

I've had a 1995 Jeep Grand Cherokee Laredo, and now I have a 1998 Laredo, TSI. Night and day, the 95 was a lemon from "H ", and I got rid of it as fast as I could. It got me for over 3000.00 in repairs, your leak problem included.

The 98 I have, the only thing I've changed is the battery. Lucky me, trade the old in for the new. It always works.

Jeep I think is one of the best made SUVs, but there are a few out there that are lemons new off the lot or used. We got stuck with a lemon. When your ready try a new one, you'll like what you find.

27th Aug 2003, 09:31

I have a 1997 Jeep Wrangler with the same wet passenger floor problem. Is this a similar fix?

21st Sep 2003, 13:39

I had the same "wet passenger side floor mat" problem in my 1996 Grand Cherokee this spring. After using the detailed fix provided by the instructional comments of Jul 30, 2002 I have had a full summer of AC with no dampness or leakage!! Thank you!!

I would add the following remarks to the process:

1) Most of the debris blocking the drain was not in the drain itself, but vertically up the "V". So, gently poke upwards to make the debris fall downwards.

2) Before plugging the drilled hole, run the car for 1/2hr with the AC on to verify that the condensate does indeed now drain out the "V" properly, and allow any big debris to pour out the 3/8" hole rather than block the drain. I jammed a large clear plastic cup under the drilled hole so I could observe it.

3) At the hardware store, the NPT plug was labeled as a 1/8", not a 3/8", in order to fit into the 3/8" drilled hole.

4) Seal around the 'donut' gasket behind the "V" with the black silicone as well. Mine appeared to be dried and cracking a bit with age.

5) Dry out the carpet and the underlying matting very well. I sprayed the undersides of the carpeting and the matting with a household bleach spray to fend of any mold growing.

I bought my 96 GC with 70k miles. At 130k, the 6-cyl engine is a rock and doesn't burn a drop of oil. But I have had to replace:

- AC evaporator

- catalytic converter + muffler

- power steering pump

- stabilizer bar links

- rear differential seal

- radiator

- brake rotors (twice)

- one ball joint.

I love the car, but it does seem to have its share of maintenance issues. I am confident it will last me another 40k miles easily, and I expect less investment in maintenance than in what payments on a new car would be.