got something started happening on my 1.8mp3 in the last few weeks, basically if im just coasting down county lanes without much right foot, up to about 60mph, the temp guage starts dropping from half down to just above the cold box on the left.

if i get into traffic it will come back up to half for a while, then sink again. Now this hasnt happened before, and i have owned it for the last 4 1/2 years so i know what the history is etc. as soon as the cars stopped, within 30 seconds you can see the guage start fluctuating, give it a rev, it picks up slightly again.

I dont hear the fans kicking on so i dont think that they are on "contantly"

So do you think its the temp sensor on its way out? is it ok to leave it as it is or could it be overhating and me not know it? Could this be reducing my mpg as i think its dropped a bit but as its started turning cold, could just be that, more electrics, lights, demisters etc etc.

oh yeah, and is it true on the 1.8 you have to remove the alternator to change the sensor?? whats all that about!

cheers for your help folks!
ps the only thing from 5-60k miles i have had a problem with is each side light blowing, so she's been a trusty girl

Could affect MPG, but I am not sure if it has a sensor for the ECU and a seperate sensor for the gauge.

Important tho is to know if its a petrol or diesel!?!?

Piggy

oh yeah, its petrol!! according to haines there is a seperate sensor for the guage which is behind the alternator

I am quite the sure the main sensor is in between the spark plug wells no2/3.

It tends to have little oil/coolant leaks and the well can fill up and bit and then give mixed signals.

However it all can depend if there is a seperate sensor for the gauge...have you looked to see??


Piggy

cheers, ill have a look between the plugs and see if i can spot anything.

try n c the other sensor too...Haynes aint as great as some think!

[quote name='InstructorPiggy' post='50614' date='Nov 25 2009, 09:44 AM']try n c the other sensor too...Haynes aint as great as some think![/quote]
any news on this post yet as i seem to have same thing happening on mine