What is this gurgling sound? Most of the time, it fishes well on the first launch. Meanwhile, the coolant is missing from the tank.

 

Skoda Octavia 3, 2014, 2.0TDI, CKFC

The gurgling sound is air in the coolant going to the heater matrix behind the dash. Would need to know other symptoms to help diagnose what’s causing the coolant loss. Lots of things could be causing it 

On 04/05/2024 at 21:25, T07 said:

The gurgling sound is air in the coolant going to the heater matrix behind the dash. Would need to know other symptoms to help diagnose what’s causing the coolant loss. Lots of things could be causing it 

Any previous posts you could point me to regarding fault finding please? Or the correct search term for the issue.

Picked up a 2018 vRS estate last week and have noticed this very same noise!

Stumbled upon this gold mine of a knowledgeable forum while trying to identify what the heck the sound was!

Worth searching across the other mqb cars which also have the issue- Leon’s, golf’s and a3s. Search for blocked heater matrix, leaking charge air cooler, leaking egr cooler, water pump failure and you should bring up some old threads 

Edited 30 May, 20242 yr by T07

There is some kind of airlock. Check the header tank levels. It's worth checking to see if the Silicone 'bag of death' has split in the header tank. If it has, you need to get a coolant flush done asap, otherwise it will chaos with silicone getting into the cooling channels on the block etc.