Temp gauge problem

[gtirobbie]

My golf seems to be taking along time to get up to temperature, it's a 25mile drive to my work and the needle still doesn't quite make it halfway on the gauge, if I put the air con/heater on it goes down even further, I've tried replacing the coolant temp sensor but it hasn't made any difference, also Its coming up with the fault code 16500. Any ideas what is causing this??

[harlemex]

You need a new thermostat matey. 

[jamie16v]

i just looked up the definition and it cam up with this..
Definition type  Definition
VOLKSWAGEN  Engine Coolant Temperature Circuit - Range/Performance Problem  
i am unsure exactly what could be causing this.. try changing the thermostat? perhaps its stuck open?..

[gtirobbie]

Ok cool, is this an easy fix on a 1.8t?

[jamie16v]

pretty much yeah!

[harlemex]

I just did mine. Very fiddly. You need really small hands and thin fingers. Remove engine and inlet covers, drain coolant, two bolts on the flange next to the alternator but very restricted area. I used a quarter inch drive socket and universal joint to get to the bottom one. Replace stat and seal and your ready to put it back together.  

[gtirobbie]

Il give that a go at the weekend, thanks for that!

[richw911]

http://www.golfgtiforum.co.uk/index.php?topic=101783.0