Normal operating Temperature

[Smith_S2]

Gents,

After driving back from the meeting on Sautrday(scottish S2 meet) i was stuck in the traffic over the Forthbridge, 1hr or so, coolant temperature was reading fine just over 90'C and the fan was kicking in, all was well. But when i was out of traffic and heading to Aberdeen taking it easy 70-75mph my reading on the dash was just above 50'C.
I think there could be a problem with the sender. See pic and see what you guys think im a bit confused
I arrived home and whilst driving around town for a bit the temp came back to normal again. Checked coolant level and it's ok.

I'm a bit worried to drive her at the moment incase she over heats even though the radiator fan is kicking in!

If it is a sender problem does anybody have a part number?

cheers
John

[Rusty]

Looks like a weak thermostat to me, happened on mine 2 years ago and the cooler winter air really shows it up. New thermostat put mine back to where it should be. HTH

[Animal Mother]

Takes 20-25 miles for mine to get up to 90c in the mornings, and that is manly at motorway speeds with about 3-5 miles of normal roads and stationary traffic. Seems to be a similar thing to your problem. Could it just be that our cars are really efficient at cooling? Have we got thermostats jammed open?

[Animal Mother]

Looks like a weak thermostat to me, happened on mine 2 years ago and the cooler winter air really shows it up. New thermostat put mine back to where it should be. HTH

Where is the stat and is it easy to change?

[mdm]

had this problem with mine, i changed the thermostat and this fixed,

i can't see it being the sender, for the simple reason you have described it as working, it show 90 when it should and drops down when it should.

[mdm]

Where is the stat and is it easy to change?

wouldn't say it easy, but it's differently not hard. hardest thing for me was getting the rad out. after that it was simple.

[Animal Mother]

wouldn't say it easy, but it's differently not hard. hardest thing for me was getting the rad out. after that it was simple.

Where is the stat?

[Acidburn]

At the front of the engine there is a pipe above the alternator which houses it. IIRC two bolts to take that off and get to it. Just lack of space is a prob at times.

[Smith_S2]

cheers guys, looks like i will get that done when i do the Samco water and boost hoses.

John

[A80Avant]

easy to check the thermostat,have the car run slowly up to 70degr. then stop,get out of the car and feel the front water tube in front of the AC condenser that goes to the thermostat.As soon as the thermostat opens there should be heat on that hose.
If the thermostat is open all the way and stuck,then the heated hose will appear immediatelly after the car runs on idle for 5min or so,just for the temp to begin to rise on the gauge.It is supposed to keep that hose cold until the thermostat opens.Then it begins to get warm.
Other than the thermostat could be your MFTS switch which is known to loose ability to show the temp correctly over the years

[Skaala]

same problem here...are going to have the termostat changed.
Another way to check it is to let the engine run for a bit, and then turn it off, wait a few minutes and start again. If the engine is warmer (no water circulating an cooling it) the termostat is most likely jammed open. Mine was fine durin summer, but cold winter air makes it too cold.

[Animal Mother]

Does anybody know how big a job it is to replace the 'stat on the UrS4/S6. I know it is a pain on the S2 due to the aux rad, is it as bad a job on the S4/6?
Do you need to mess about with power steering pumps and alternator etc?

[waad_uk]

How to change S2 Thermostat...... http://www.s2-audi.co.uk/tech_articl...at_replace.htm

[Paulgo]

Not wanting to decry in any way Mike's excellent write up in the link above to his site but it is possible to change the stat without removing the rad, which greatly simplifies the process Jas did his the other week and posted it here and we did mine the same way last year. scroll down to post #13 for a run through which includes the stat replacement. Good to have a spare set of hands to hold the power steering pump up when freed and keep it out of the way (my job )!

cheers

Paul