I bought this used car about a month ago. I was told that they changed all the fluids and made sure everything was running ok. About a week after I brought home I started to hear a noise in like my dash or somewhere around there. I only hear it when I first put my car in drive and take off. It sounds like water or some sort of liquid is moving through my dash.

1 Answer 1


The evaporator drain in the HVAC case is clogged.

Basically, the condensation that comes off the air conditioner when running collects in the plastic case that surrounds it, and then drains through a small rubber tube through the firewall or floorboard area to the ground outside.

Because this case usually collects fresh air from outside (usually the vents on the cowl, directly under the windshield outside) it also collects dust, dirt, leaves, pine needles, etc.

These clog the drain, the condesation (water) level build in the case, and this causes the liquid sloshing noise you hear. Because it's liquid, and it's sloshing...

This is a relatively simple and inexpensive repair that most any shop should be able to provide. Basically, you unblock the drain from the outside, and empty the nasty contents of the HVAC housing.

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    You can usually do this yourself, if you can find the drain tube, which is usually located just under the air box on the passenger side of the car. It will be a small rubber tube. Some of them are straight, but ones I'm seeing for Dodge's look like they come straight out of the firewall and are angled down from there. If so, just pull the rubber off the firewall and then run something long/thin into the hole. You'll know when you've reached pay dirt, because you'll see water come rushing out. You shouldn't have to dig too deep to get it to flow, considering what I'm seeing. Commented Aug 16, 2016 at 21:40
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    @Pᴀᴜʟsᴛᴇʀ2 is very correct, but it helps to have a lift. Please do not look directly at the drain hole while poking at the blockage. Although this job is easy, it's also one with a potential yucky scummy water and rotting debris bath. Ask how I know. Honestly, if I wasn't a mechanic I would pay somebody else to do this job. Now that I have teenagers, I "teach" them how to do this type of job... from a distance.
    – SteveRacer
    Commented Aug 17, 2016 at 3:23
  • Absolutely great points, Steve. I think we who have done this have experienced what you're talking about first hand, lol. My buddy cleared my Z28 AC box for me and ended up with a face full of water, lol. Not funny, but I had to laugh anyway. I don't think he appreciated it, lol. Commented Aug 17, 2016 at 21:19

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