Sloshing noises from dash area?

[Safety Guy]

This isn't a repair situation--yet. If might signal something going wrong though, so I'd better ask if anyone has ever heard this or knows what it could be.

In the past month or so I've heard some sloshing noises from my dash upon cold startup and then stopping the car. It's as if liquid were in a metal pan and sloshes upon the stop. No leaking has materialized inside or outside the car, and only a faint smell of antifreeze was present once or twice. (Not sure if that is connected, but I haven't smelled anything lately.)

The car runs fine and I've replaced the coolant in my car once upon returning from Madness, where I drained the old nasty coolant and put in mostly water to begin cleaning out the system. I have around a 50/50 mix of antifreeze now and there are no cooling issues.

I'm thinking "heater core," but again, no leaking to be seen. Would a leaky core leak into another vessel within the dash? If so, why would it not slosh around constantly instead of only a little bit upon cold startups and stops? I don't get this sound any other time, so it's not constant.

I'm also thinking it could be the heater core being "cleaned out" of gunk as the car runs at a certain time and temp. Maybe that's it?

Any ideas appreciated. I've never heard of this before.

Karl

[David88]

Could be the tub area below the windshield is not draining. Drainage holes maybe plugged with leaf debris. Did you look down past the wipers through the grille.

[william]

Check you coolent level my truck will do this when its low.. You can hear it flowing in yo the heater core.
Second thought do you have ac ?? If so you may have some water taped in the condencer box , its suppose to drain from that little black hose that comes from out of the fire wall

[Safety Guy]

Thanks guys.

No A/C. Also, the sloshing is not constant.

I just now went to check the cowl tub area any way. Nope, it's all clean & dry down in there.

Coolant levels have checked okay.

Any more ideas?

I'm thinking it just may be some muck in the heater core, or maybe the muck caused a "bubble" somewhere on the heater side of the equation. Does that sound plausible?

Karl

[David88]

Yeah especially if you just did work to the cooling system as you said. Likely just bubbles working through the system. Good ear! Its always good to listen to what your car is telling you.

[jake88maro]

yes, i've had this same symptom in my dodge plenty of times, just the coolant being pumped through the heater core!

Check you coolent level my truck will do this when its low.. You can hear it flowing in yo the heater core.
Second thought do you have ac ?? If so you may have some water taped in the condencer box , its suppose to drain from that little black hose that comes from out of the fire wall

[FestYboy]

Karl, you likely still have some air in the core, you're hearing sloshing/cavitation from coolent moving through air within the core. i suggest driving aggressively to help push the latent air through the core and out to the rad where it can be pushed into the overflow container.

[bravekozak]

Have your rad cap pressure tested.

[Safety Guy]

Thanks again all. I'll not worry too much about it and keep tabs on the coolant level, etc.

Karl

[zoe60]

If it makes you feel any better, mine does it too. First thing in the morning. Been about a year and it hasn't been a problem yet.

[Safety Guy]

Thanks Zoe; nice to know!

Karl