Hello,my 2.0 lt. 2011 dsg hardly ever reaches working temp(90 degs on the water temp guage),and when it does the temp will drop down again swiftly to around 40 or 50 degrees when going downhill,even on a short stretch.

I was sure it was a thermostat stuck in open position problem.Had the thermostat changed to a new one (hell of a job,wish you all never to have to).

To my surprise,the same problem persisted,so alas, it was not a thermostat failiure that cost a small fortune to do.

Please,does anyone have any idea what the problem is?

Really grateful and thankful for any help.

Raphael

In the good ol’ days it’d be a relatively simple job for a spanner wielder but it’s probably something that needs a diagnostic tool, or perhaps just a new battery......maybe the gauge itself.    Sensors are in control these days. 

Didn't someone say recently that there are two thermostats?

There is a small circuit thermostat for the head that heats quickest and provides heat to the heater and also a main circuit thermostat near the water pump for the block.