I have a 2005 Monte Carlo SS. Over the last few months is when the sound of water under the dash has occured. Haven't noticed any wet areas on the carpet and no stale water smell. Some days are louder than others and does it more when turning or going over bumps but does it when going staright.Any ideas.

 

Are you sure it's not water in your wheel wells?

 

I will look in to see if it could be that

 

The carpet has a very thick piece of foam glued to the bottom that could be soaking up the water & hiding the actual amount of water that is there.

 

Are you letting your engine warm up before driving?

 

When mine made a similar noise it was a leaking heater core. Sometimes when you would rev the engine then stop you could hear water sloshing around. It went about a month before it started leaking out. If thats what it is It's a pain in the butt to change and if you can afford to have it done for you it would be worth the money. Also I had to order my heater core no one had one in stock.

 

My bf's 04 SS makes the same noise.. i just think its coolant passing through( usually happened around corners.. sound came from pass side.. by heater core, ^^^ he did end up needing heater core fixed eventually

 

check your coolant and washer fluid, i replaced both of those when mine did that and it went away