Sloshing sound behind dash

[20LTZ13]

im not sure if this belongs in this catagory but ive been notcing a sloshing sound coming from the pass side of my dash for about a week now. It happens when i accelerate or come to a stop. Has anyone else been experincing this? Im wondering if my evap case is full of water due to a clogged drain.

 

[Chrish051873]

i have seen this before, personally i have never had it.

I think it came to air trapped in the heater core, if im wrong somebody please correct me.

 

[rcmn0022]

I believe that most people, that have had sloshing sounds coming from the dash, have been diagnosed with air in the coolant lines for the heater core.

 

[20LTZ13]

ok thank you, ill set up an appointment with my dealer.

 

[SuperFudd]

Put another way, your coolant level is low.

 

[20LTZ13]

I checked the res. and its up to the full cold mark with the engine cold?

 

[Stew]

Save yourself the trip, it is a small amount of air going through the heater core, which will eventually work itself out. The coolant expansion tank is a continuous purge type, air will work it's way in there and be removed from the rest of the system.

 

[MikeM]

I had the same issue. it was low coolant. Soon as i topped it off i never heard it again.

 

[Luv2xlr8]

I have this same problem, I even parked the car on an incline and open the cap and let the car run for 10 minutes to let all the air bubbles out or at least I tried and it sorta worked. I still get it a little now and then.

If someone does take it to the dealer, let us know what they say.

 

[20LTZ13]

Ive got an appointment for tuesday to look at that and this mettalic rattle in the pass side door. Ill let you know what they say.

 

[JamesMay]

I had the same problem, then my heat stopped working. Mine was a bad thermostat.

 

[SuperFudd]

The 2.2L engines such as in my dearly departed rustic green Plymouth Sundance had similar situation. Air would build up in the cooling system. When air would build up, hot water/coolant would not reach the thermostat so it would not open. The fix was to drill a 1/8, (or was it 1/16?) inch hole at the top edge of the thermostat allowing the air to bleed off while the thermostat was closed.

 

[NewZJ]

Most or all modern thermostats have a tiny hole to allow air to pass through the thermostat for that reason, a perfectly sealed thermostat wouldn't be functional if it was in an elevated position that would allow gases to accumulate around it

 

[Sonic]

Dealership has had the car since 7am this morning. My service advisor just called. He said they replaced the water pump because it wasn't circulating to specs. That didn't completely solve the problem, so now they are in the process of changing the thermostat.

All this when I merely thought that the coolant was low or that I had air in the lines. They were only going to bleed/burp the lines but quickly realized that there were far larger problems.

I love my local Chevy dealership. Big props to Walt my service advisor and Kelley Chevrolet.

 

[20LTZ13]

Dealership has had the car since 7am this morning. My service advisor just called. He said they replaced the water pump because it wasn't circulating to specs. That didn't completely solve the problem, so now they are in the process of changing the thermostat.

All this when I merely thought that the coolant was low or that I had air in the lines. They were only going to bleed/burp the lines but quickly realized that there were far larger problems.

I love my local Chevy dealership. Big props to Walt my service advisor and Kelley Chevrolet.

Im taking mine in on monday to get looked at. As a service advisor myself its nice to see someone showing the love... trust me we all appreciate it.

 

[rcmn0022]

I got mine looked at. I mentioned the sloshing sound and the fact that it has been taking longer to heat up. They performed some kind of miracle update that fixed the sloshing, the speed of engine warmup and my traction control acting weird.

I'm not too sure how that they are related but maybe the update for the one also had an update from before that fixes the other

 

[SuperFudd]

WIERD!
does a computer control the thermostat?

 

[SuperFudd]

qwerty

 

[rcmn0022]

WIERD!
does a computer control the thermostat?

It is an electric assisted mechanical thermostat. The electric part can allow the thermostat to open early or force it to open late.

But that is part of the ECU controls, and they didn't wipe out my tune. So I'm not sure what the update is. Maybe there is a valve that restricts the flow of coolant into the heat exchanger. Maybe that valve is controlled by the BCM and they preformed an update on it. Or there could have been a design flaw in the setup of the heat exchanger, and they fixed it somehow with an update kit of parts for it.