1.8T thermostat

[JayB5UK]

Where is it, engine code APU.
Think mine is a biut dicky, when I drive to work I have long hill to coast down, about 1 mile, my temp guage drops from about 80 deg to 65-70 by the bottom.
Have changed temp sensor, which has made it more stable and I get a reading quicker when warming up on the journey, but this otherr issue is weird.

 

[mattpanton]

According to ELSAWIN the thermostat is located in an elbow pipe that comes directly off the bottom of the water pump housing,

hope this is of some use

 

[JayB5UK]

Cheers, where's the water pump, down the front?

 

[enda1]

On the hill are you using engine braking or coasting or are you using the throttle at all?

 

[macca]

water pump is under alternator, you'll see a black plastic elbow coming out of water pump with hose attached, you need to take elbow off and thermostat will be underneath inside, need new rubber o-ring when fitting, may come with new thermostat. awesome do a lower temp thermostat for if you drive hard/chipped engine.

you can get new waterpump from eurocarparts for about £25, might be worth doing at sametime as the plastic impellors are known to break off and depart.

 

[JayB5UK]

Down the hill I am off the throttle for about a mile normally.

Will look into thermostat and water pump, I know the cambelt was done a couple of years ago but no evidence of water pump at the same time, so it has been niggling at me for a while.
Re: lower temp 'stat, my car is chipped, but after I de-catted the car, the temp dropped instantly from a normal of 90deg, to just under 80deg, so not really worried about that, just that it fluctuates a lot like on the hill I mentioned.

 

[Rev-head]

If your Thermostat was gone you would be either running cold all the time or over-heating.the best test is to have the car idling outside and watch the temperature got up when it is sitting tickover it should stay at 80-90 all the time give or take ....the reason the engine temp is going down is your are idling down a hill with cold air blowing through the engine cooling it with no extra load on the engine.............Does it happen any other time ?

 

[JayB5UK]

No it doesn't really do it any other time, I thought it was obviously cause of no load on the engine and all the cool air, but my mate's had Golf 1.8T's and they both swore blind that theirs ran at 90 all the time and that there must be something wrong with it.
I won't worry about it then as it is pretty much good as gold all the time now, the new temp switch has helped to stabilise it also.