Liquid sloshing sound

[smithBYU85]

I have an 04 Gen II with 97k miles and I hear the sound of water sloshing through tubes/pipes when my ICE turns on. I hear it especially when I first start the car in the morning, but I hear it when the car is warm as well. I normally hear when the ICE turns on.

For example, the car can be warm or cold, I stop at a stop light and the ICE shuts off, when the light turns green and I accelerate and the ICE turns on, I hear this sloshing sound. If any of you have a sump pump in your basement, the sound is very similar to the water being forced upthe pipes and out of the house (minus the sound of the pump, I hear no mechanical or electrical noises with it).

I haven't noticed decreased performance from the car, my MPG is normal. I have only heard it for about 2-3 weeks. I won't accept answers saying it's getting colder outside, I didn't hear this sound the last 2 winters since purchasing the car, and the previous owners (my parents) didn't hear it either.

Anybody have an ideas?

[vertex]

The CEL isn't on is it? If you are low on coolant, you might hear something like this, but you would have some DTC. It is probably water from the AC drain which may be clogged.

[smithBYU85]

Originally Posted by vertex

The CEL isn't on is it? If you are low on coolant, you might hear something like this, but you would have some DTC. It is probably water from the AC drain which may be clogged.

How do I get at the AC drain unplugged or check to see if it is? Forgive me, but DTC? The CEL is not on, I have no error or warning messages.

Tyler

[Patrick Wong]

Hi Tyler,

Normally there would be a couple of reasons why you would hear water sloshing around. One would be because you have water trapped in a door or the cowl assembly. However you would hear this noise when moving, unrelated to whether the gasoline engine is on or not.

If the noise is tied to the gasoline engine starting, then I would say that you have air in the heater core. To get rid of this, you would need to set the AC temp to MAX HEAT, then run the engine at around 2,500 rpm for several minutes, until the noise goes away. Then check the radiator overflow tank level when the car is cold and top off as needed with Toyota Super Long Life Coolant.

Normally you would not have air in the heater core unless the engine coolant had been replaced and the tech doing that service failed to purge the system of air. If you haven't had the cooling system serviced recently, maybe you have a leak somewhere, and this needs to be investigated.

As your car is approaching 100K miles, if the engine and inverter coolants haven't been replaced yet, that work should be done soon.

[smithBYU85]

Originally Posted by Patrick Wong

Hi Tyler,

Normally there would be a couple of reasons why you would hear water sloshing around. One would be because you have water trapped in a door or the cowl assembly. However you would hear this noise when moving, unrelated to whether the gasoline engine is on or not.

If the noise is tied to the gasoline engine starting, then I would say that you have air in the heater core. To get rid of this, you would need to set the AC temp to MAX HEAT, then run the engine at around 2,500 rpm for several minutes, until the noise goes away. Then check the radiator overflow tank level when the car is cold and top off as needed with Toyota Super Long Life Coolant.

Normally you would not have air in the heater core unless the engine coolant had been replaced and the tech doing that service failed to purge the system of air. If you haven't had the cooling system serviced recently, maybe you have a leak somewhere, and this needs to be investigated.

As your car is approaching 100K miles, if the engine and inverter coolants haven't been replaced yet, that work should be done soon.

Thanks Patrick, that makes sense. I had the car serviced at ~92k and they replaced the coolants, and that was only about 3 months ago. I will give that a try and let you know.

[smithBYU85]

So I tried what Patrick suggested and it seemed to make a small difference, but I figured it better to take it back to the dealer. After some annoyance, they confirmed that it was the engine coolant with an air pocket and they bled it for me free of charge, since they screwed up.

I still hear a bubble every once in a while, so they didn't get it 100% clean of air, but my confidence in them is pretty low. They called me an hour after I dropped it off and said it was ready, so I picked it up during lunch but the noise was as loud as before. So I had them bleed the system again, so they had 2 techs do it and they checked it numerous times before they gave my Prius back to me.

*sigh*, I think I'll find another dealer to go to...