Engine Coolant Temperature (ECT) sensor: Location?

[AntoniosM]

Hi all!
The car is an Audi A4, 2.0L TDI, from 2011. The last few weeks i have been having this strange problem. The car will have trouble starting if it is moderately warm.. If it is completely cold (<50C) or fully hot (~90C) it will start directly. If it is say around 60-70C it will start after the ignition runs for at least 5-10 seconds, and sometimes it won't start at all. In that case i was forced to wait until it cooled down to 50 and then it stated directly. After that it will run smoothly.
This felt a bit strange so i started looking around on the web and i come up with the theory that the Engine Coolant Temperature (ECT) sensor is malfunctioning, showing a bit too high temp. When it is completely cold it will pump anyway enough fuel. When it is fully warm it doesn't need too much anyway but when it is there in the middle, it thinks it is fully hot so it pumps reduced fuel and so the problem.
Also after reading the web a bit I figured this seems to be a relatively easy repair so, even if i am not very experienced car mechanic i decided to give it a try. In fact i was so optimistic that i already bought the spare part!
Unfortunately i got stuck on the very first step. I have been looking for quite a while but but I can't find the sensor on the car! Does anyone know where it is sitting? I attach a picture of the new sensor and a picture of the motor. Any help is appreciated!
Cheers!
Antonios


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[Crasher]

I have only had to do a few this new so far so you are unlucky. The sensor is in the metal water transfer pipe around the engine, it is a CAGA/CAGB engine by the look of it.

[AntoniosM]

Thanks for the quick reply!
I will look into it tonight and post how it went.

[AntoniosM]

I just had a look but I am still not sure.. Is it inside this plastic container in the middle of the picture?
Antonios

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[Crasher]

NO, that is the vacuum operated water control valve. Please, take this to someone who knows what they are doing! Get this wrong and you can end up in hospital, I did when someone left a booby trapped temp sender clip and it is not funny!