Volkswagen: Engine type & Temp Sensor, german swedish and french, faulty sensor

Question
I believe I have a faulty sensor (it jumps around even after the engine has heated. I've read many posts about this and most state it's the sensor. Would you agree?

I've located mine (2000 Passat 1.8L) in the back of the engine right before the firewall but I can't seem to find the part on the net; is it a dealer only part? When looking for the replacement part, the parts always ask whether my 1.8 is either ATW or AUG; how do I determine that?

Thanks,

Dan

Answer
your engine should be an ADR, APT or similar. it is stamped onto the head under the engine cover at the front of the engine on the inlet manifold side. I think it should be a 4 pin blue square sensor. it is available as a non genuine part but i'm not sure who would sell it. maybe you could try www.andyspares.co.uk (gsf "german swedish and french") as they supply non genuine parts (ie not vw stamped but often made by same companies who make the genuine ones).