When I put the A/C on, I get a trickling water sound coming from under the drivers dash... fan speed has no impact and it goes away within 5 seconds of shutting A/C off. Car has 55k on it, full Lexus service history.

One other thing... when looking under the hood, the sight glass on front of radiator had bubbling fluid running thru it with A/C on and car running...

I am a noob with A/C systems... what is my problem??? I am thinking this noise can't be normal, anyone else experience this? The noise is annoying the crap out of me...

Manual points to low AC charge... bubbles are bad apparently...

Thanks for the inputs!

 

low on refridgerant

 

Bubbles are said to indicate low refrigerant. Get it looked at and repaired sooner than later - compressor can die if run with too low coolant. Also don't just get a gas fill-up - take it to someone that's qualified to troubleshoot the system for leaks. Its a sealed system and not supposed to leak. I have had cars for 10+ years with no refrigerant loss or need to refill. If you just fill it without correcting a significant leak it will just lose the coolant gas again.

 

Great advice. Being a used car, who knows what has happened to it so I might just get it refilled to spec and monitor from there... maybe the previous owner had some hack "refill his A/C" and they let out some charge...

 

I had this sound on my GS once. it was low on coolant =P

 

That is encouraging. Autozone has a kit with gauge for like $35... so you don't overfill the system... I'll hook that up and confirm if I have a low charge and then fill it... then monitor for any leaks, that is my plan. I'll report back if the noise is vanquished with a freon charge or not... thanks to all.