Water Noise in Dash

[Renegade2k]

I have a 2000 Intrigue with the 3.5L and last winter it started to have odd noises. Early in the winter it started sounding like water when I accelerated, I thought maybe it was melted snow that was moving. That wasn't it.

Later in the winter it sounded a little like Ice Cubes flowing. This freaked me out that my coolant was freezing . I checked the bottle that I had added with and it was frozen mixed 50/50 at 26 degrees. So I decided to switch to green coolant instead of dex-cool. Flushed 3-times with water and then used machine to flush in 6 gallons of green.

The water noise is still there in warm weather.

[Mickey#1]

Catalytic convertors can make a rattling noise when bad. Try shaking it or have a muffler shop check it out.

[Renegade2k]

This is a water noise, not a metallic rattle.

[dizzle1]

My car does the same thing I thinks its the HVAC in the winter the coolant is moving around like water making water sounds I've heard that their is a chance I have air in the system. Car runs fine always a little below the half mark as warm normal operatind temperature. I am using dexcool

[Renegade2k]

The reason for changing to green coolant was out of frustration, and you can get it anywhere in an emergency. I've had this car for 4 years and it just started making noise this last winter. the noise goes away after a few minutes.

[harmankardon35]

could have air trapped in the cooling system

[BNaylor]

Is the noise (sloshing or gurgling) in the dash area? Probably coolant circulating through the heater core since it is supposed to flow all the time regardless if heater is used. Sometime a flaky thermostat not opening properly (stuck partially open or slow to open) can cause it. Plus low coolant level so check that. Sometimes flushing just the heater core resolves the issue.