Just wanted to let the community know/people who are expereincing these bubbling sounds that after driving my car in hot conditions or driving hard under boost for a while, I just let the car cool down by driving in vaccuum for ~5-10 mins very gently but the main thing here is NOT TO LET YOUR CAR SET BEFORE YOUR SHUT IT OFF.

Iwould do this and once the car was off it would bubble like ****. Now i just pull into my drive way and into the garage and turn it off, no BUBBLING wat so ever, even on a 31 degree celsius day. I often let the fans run thos for about 2-3 mins afterwards..
So if your having coolant bubling issues and not over heating, try just shutting the car off and turing on the fans afterwards..

 

i just got my car, and i hear the same thing your describing. But i dont have to be driving it hard, and i usually coast as far as i possibly can before coming to a stop,usually about a minute. And i hear "bubbles" or water actually moving? i meant to search earlier but forgot. so, what is this? ive been wondering.

 

its just the coolant decompressing i believe, and just slowly flowing around in the pipes, and stuff. Nothing to be worried about.

 

Mine does all the time. No biggie!

 

I usually shut the car off immediately. Then I turn the key to ignition and the fan would come on and like others have said leave than fan running for a few minutes or until it stops then take the keys out.

 

Swapping out the fan thermoswitch for an FC (direct replacement) or Miata (requires crimping 1 wire) thermoswitch will lower temps in general, and get rid of the boiling with no special techniques required. It worked for me.

 

it could also be you're low on coolant, but not low enough to trigger the light/buzzer.

 

My overflow tank is filled to the brim,
and my coolant level seems to be alright.
car only boiled coolant if i let it sit for 1-2 mins idling before shut off
not i jsut maybe let it sit for like 10 seconds or so while i get my stuff together and then driver her in an shut her off and turn on fan for a few
no boiling wat so ever

 

I would burp the system if I were you, just in case you have some air in there. While your at it, you may want to look into changing the rad caps, and thermostat as well (cheap insurance).

I'm also a huge fan of the FC thermoswitch mod. IMO, this is the easiest and most effective mod you can do to the cooling system. For 50-60 bucks, and a couple hours of your time, you can get your car running 10 degrees cooler.

 

^^^ +1 - my coolant used to bubble after driving it... burped the system (took a while) and it went away...