Temp sitting at 90 then 85 then gets even lower :(

[MrRogers]

Evening all,

I seen a topic on this a little while back a couple of people have some trouble with their temp guage dropping very rapidly. Its started to happen with mine. Iv had the thermostat changed last year so i would like to say thats ruled out..i changed this due to my car constantly over heating when sat in traffic but when in motion it was fine again along with a new cambelt and water pump..that is still happening occasionally but i am now getting the reversal of it when in motion the temp guage sits at 90 then 85 for quite a while then all of a sudden yesterday when on the motorway it went town stupidly low, also the heater wasnt that hot neither.

I havent had the chance to give it a scan yet but would anyone be so kind as to shed some light onto it? I got a funny feeling could be the Temp sensor due to sometimes im smelling petrol through the vents, still occasionally over heating are these all the sines of a dodgey Temp sensor or is it worse?

Cheers.

[xxChrisxx]

If it gets to 90 in traffic but drops when you are on the move my money would be on a thermostat thats failed in the open position.
Does it take a while to warm up?

[daz veedub]

seems to be a mk4 gremlin this topic 

temp sender or thermostat or even both or could be wiring on top of temp sender

[jcook6788]

I was told if the temp sender fails the needle wont move on the temp gauge? is this true?

[tg1]

think i might have a spare temp sensor lying around at home you can test it out, save you buying one if you dont need it?

only a 30 second job to swap it over

[xxChrisxx]

I was told if the temp sender fails the needle wont move on the temp gauge? is this true?

Yeah the needle wont move if the sensor sends no signal. An intermittent fault would make the needle drop to from 90 (at running temp) to zero.

This is what makes me think it's more likely the thermostat. They are fairly easy to change, just remember to buy a new O ring.

[houston]

temp sender wouldnt affect the heaters tho, id say redo the thermostat, the winter could have killed it, they dont cost much either.

not losing water are you?

[turbomick]

100 percent with chris thormstat doggy again did u get a chep one

[MrRogers]

Not visually loosing water as such but the golf does tend to use quite abit of coolent i probably end up topping it up every 2-3 months (thats a rough idea). I had the stat changed going back last summer thinking this would solve my over heating problem but it still does it when sat in traffic with "STOP" message being displayed.

I had the cam belt and water pump changed about 2 months before the stat aswel. 

xxChrisxx the golf does tend to take quite abit of time to warm up aswel. The "warm" air was only noticed a couple of days back when driving up the motorway when the temp guage was at its lowest i had ever seen it (two notches up from the bottom line)

The garage is a very reputable VW/AUDI specialist in Bristol which apparently acording to the manager uses all genuine VAG parts.

I also ran a scan on the golf going back on the 23/01/11 along with the list of codes it through up this:

16503 - Engine Coolant Temp. Sensor (G62): Signal Intermittent
            P0119 - 35-10 - - - Intermittent

Could this be an underlying issue that could contribute?

I wouldnt have any means to stand on if i was to complain to them that the stat was broken already i suppose?

Thank you TG1 for the offer but i think i mite just buy one to see if it clears it up there not that expensive are they?

Thank you everyone for the prompt replys 

[Wayne]

I think your thermostat has failed.