Audi A3 1.8tfsi -- Coolant Temp Sensor

[Jonny weggie]

Hi there
Been trying to find the coolant temperature sensor on the 1.8tfsi 09 plate but can't seem to locate it can anyone en-lighten me to where it's situated.
Thank you in advance.
John

[audiS3saloon]

Coolant sensor is in the Coolant expansion bottle. Let me guess you get a warning of low coolant on start up, coolant was okay.
I used to get this once every 3-4 weeks on my 2010 A3 1.8tfsi only when parked outside overnight.
Mentioned to Audi dealer when it was being serviced and the service advisor had same problem with his A3. Sold my car a few months ago to local dealer who has same problem with a 2009 A3 Petrol he had in stock. Audi quoted my £500 to replace the coolant expansion bottle (I declined !)

[Blaster72]

Temp sensor isn't in the bottle, that's the level sensor.

Anyway, this might help

http://hubpages.com/autos/How-to-Replace-a-Tempera...

I changed one on my old 1.8 Audi A4 and even though I knew where it was supposed to be you couldn't really see it. Had to change it mostly by feel.

Mine was struggling to start when cold, temp sensor was stuck at about 50 deg C when I scanned it.

[Jonny weggie]

Thanks very much Blaster72, will have a go at it when weather warms up a bit from 3 degrees.
Jonny

[Jonny weggie]

Update -- I am at a loss now to where the coolant temp sensor is on my sons A3 1.8tfsi 09 plate located as per blaster72 information giving, there is nothing at all down that side apart from a blanked off hole which might have held it but not now.
Looked everywhere else ( nothing) so if anyone else can shed a light would be appreciated.
John

[Rich_W]

If you look down below the inlet manifold you'll see the water pump

Pic from internetz


Top left is a GREY multiplug. IIRC that's the temp sender. Double check with an online VAG parts list.

[Jonny weggie]

Thank you for picture, I'll give it a go when weather gets better.
John