Coolant Temperature Sensor

[SlothBurger]

Recently the VW dealer replaced the coolant temperature sensor in my T6 Kombi. It had been fluctuating when moving & never reaching 90 degrees. Today I was idling the van after driving & bringing it up to temperature (90 degrees) & I notice the temperature dropping back to around 80 degrees while idling.

I haven't seen this happening previously. On any other VW or Audi I've owned it stayed at 90 once it had reached that temp. when idling. Wondering if normal on T6's?

 

[n10n]

Usually it stays quite well at 90° once up to temp. That said, I recall it sometimes hovering slightly under. I wouldn't worry too much if it stays at 90° when driving, coolant levels are normal, you get decent hot air into the cabin and it's not eg running the fan all the time.

You should also know the temperature gauge lies, it shows 90° for coolant temperatures between 75° and 105°. This is done to not alarm drivers of minor temperature fluctuations. If the temperature gauge shows 80°, the real coolant temperature will be around 70°. See [T6_measured] Winter specialities