Hello,
I have a 98 A4 Tdi with 90K on the clock. Recently, a flashing red light (water with thermostat in it) comes on when the engine is warmed up - after about 10mins. When I inspect the coolant reservoir - it is full and a orange color. The temp remains in the middle at 90.

History:
Red light came on, upon inspection - reservior was empty - filled up with 50/50 normal coolant & water.
About two months later - same thing happened - again filled up with coolant & water.

Now - the light comes on - but the coolant level is up to the top!!

Has anyone else come across this or something similar?? Please help!!

Thnx,

A Novice!

 

Maybe a bad coolant level sensor at the bottom of the reservoir?

 

Thanks!!
Will give it a go! Do you happen to know if its hard to get to replace or expensive?????

 

thats what I was thinking.

 

Wait a sec... you filled the reservior and it was empty 2 months later?

You may have a more serious problem than a faulty sensor.

 

Yeahbut, I've seen the senser go bad and the coolant leak though the sensor, not the o ring but the sensor.

 

Thanks Guys - great inputs!

Yes, correct reservoir was empty after approx 2 months.

I am getting a quote from a dealer on Thursday for a new sensor and replacement - and will keep you posted.

Interesting to know the coolant may also leak through the sensor - as this may be whats causing it to go bad!

Also, it only happens about 75% of the time I'm driving and only when the engine is warmed up after about 10mins

Thnx,

Paul