1997 Ram 4x4 5.2 L Been noticing my passenger floor is getting very wet. Not all the time. Thought it might be from rain, but tried different things during the rain and it's not coming from rain, or car washing. I think it's coming from when I use the heat, I hear and have checked that the air conditioner compressor coming on and off during the time I'm running my heat, which doesn't make sense, and the hose for the aircondition is cold as hell and condensating. The coolant level is not changing it's stays full, this is been going on for over a year. Just tired of the floor being soaked. It seems like its coming from the heater core but I should be loosing coolant and I'm not, should my compressor be cycling during use of heat? Hell I don't know.

 

Its your heater core. Its a very small leak, and it wouldnt cause a noticeable loss of coolant. Your A/C compressor should cycle when the heat is on, its normal.

 

+1 since you said pass. side, i cant immidiatly say heater core

 

well if u doing thinks it the core check your thrid brake light

 

It does not get wet just sitting, like in the rain, it sat like a couple of days in the rain. Only seems to happen when i run the ac in the summer and the heat in the winter like the defrost. I'm trying to narrow when this happens. It don't rain or i don't wash it for a couple of weeks and it still gets wet so i can rule out the third light. I just put a turn down elbow on the drain on the firewall to keep the air from blowing water back in the box.

 

If your windows begin to look like they have film on them while the heat is on then its your heater core. Also you will begin to smell antifreeze as well as seeing smoke coming out of your vents.

 

Yes if you smell a little anti freeze and get like a filmy residue on your windshield your heater core is done.

Otherwise check the following, even if you think it is a leak from outside.

-Third Brake light
-Weather stripping
-Windshield, and Rear window seals
-A/C drain hose(may be clogged, coat hanger and compressed air is your friend)
-Check body seems under plastic cowling that houses the wiper components. This is where my leak was.

 

It can be perfect weather outside and it will still soak the floor no rain or car wash for weeks.

 

Did you check your heater core like the others above me have said? That's what it sounds like to me as well.

 

My passenger side carpet was wet and it was a mild drip from the heater core. Easiest way to prove it is to lay down a plastic mat for awhile. I had a small puddle of anitfreeze. Run a bottle of Bar's radiator stopleak or similar if you don't want to replace the heater core right away.