Boiling coolant, desk temp 90def, no radiator fan switched on

[Silv3r]

My coolant got BOILED with visible small smoke, reached the cap (full reservoir) and leaked away from occurred crack in the reservoir...

The temp. On desk 90 deg, the fan did not turn on, outside temp. around 15deg and it happened when I stopped... I did not even drive fast

What could happen?

My Audi drives me crazy last days ...

Wysłane z mojego SM-G950F przy użyciu Tapatalka

[Silv3r]

Radiator fans are OK

Where to find the coolant temp sensor and how to test it?

Wysłane z mojego SM-T280 przy użyciu Tapatalka

[bwhite2332]

Coolant temp sensor is at the bottom of the expansion tank. If it comes out, so will all of your coolant


Sent from my iPhone using Tapatalk

[Silv3r]

I found the issue... The cap (!)

Wysłane z mojego SM-G950F przy użyciu Tapatalka

[JamesRS5]

That will do it, it’s a pressurised system so with a failed cap the water will be allowed to boil where it would normally boil at a higher temperature.