Audi A3 Water Temperature Showing Wrong

**power33** · 20th February 2011

Hello,

Only a few weeks ago my temperature gauge started showing the normal operating temp (90) on the next notch after 90. As seen in the picture below: Also the car does not overheat and the fan comes on etc.

I havnt changed the temperature sensor yet because when i unplugged the sensor the water temperature level didn't drop all the way down to the bottom it just stays on the next notch up as seen:

Does anyone know what this problem could be.

**bez101** · 20th February 2011

your clocks need a clean

20th February 2011

they normally hit 102 (at the engine, not radiator) before the fan kicks in, all audis display 90 on the dash until at least 105 is reached (i believe), they did this to stop people from telling them there car was over heating.

your car is clearly hitting 105+ at the engine, but believe me, if it isnt getting any hotter your not doing any damage, my guess is that your slow speed fan resistor is not working........ do you notice the car fan suddently go from off to supper fast when you let it sit and idle for a while?

i take it it sits at 90 whilst driving above 20 mph

check the following first....

coolant level
make sure you have decent coolant in it and not just water
make sure the coolant cap keeps pressure in (when you release it a LITTLE you should hear a gust of air release)

if that dont help, you'l lneed to check that both slow and fast mode works on the fan....

**power33** · 20th February 2011

Whilst driving even over 20mph the temp sits on the same point, and even before I start the engine, e.g if I leave the car for 2 days, the temp gauge already shows 70.

**ovga** · 11th June 2011

I've just found this post by google. Do you have a solution?

I've got a similar (slightly worse) problem since bought my used Audi A3. Needle always starts at 70C when cold and sits around 100-105C when normal. Then after staying there for 10-15 minutes temp gauge goes crazy, goes above 100 and back to 100, stops somewhere 100-120, sometimes hit the high end (140 off the scale) and the temp warning beeper comes on.

Temp sensors (both at cylinder head and in radiator outlet pipe) were changed, thermostat was changed but did not help. At a garage, it was confirmed that pipes are around 90C (was measured) and concluded being a dash pod problem... I haven't tried an Audi dealer yet. My current understanding:

- This must be a display error as coolant always seems normal (not boiling/no coolant loss even driving for 30min at "140C").
- Going above 100C may be related to colicabcadam's post. If the coolant is supposed to be a bit colder, it won't go above 100C. Eg. driving on a motorway with constant speed is usually OK, "overheating" appears when going slower. "Overheating" also doesn't appear if heating is turned on at least 1/3.
- "Overheating" status disappears and reset to 100C if stopped and turn off ignition for some minutes.
- Very rarely it fell back to 90C for a short time (minutes).

Any idea? Costs?

**Ay3** · 16th June 2011

I have a fuel and temp gauge problem on mine too, seems to be quite common from what i can gather. Faulty dash pod and big money from Audi.

If you are able to remove it there are firms around that offer a fix. Search Ebay for Audi A3 dash.... Mine also has a faulty display so will cost about £180 to fix