Audi spewing green goo, fan is out to lunch

[Zoot531 at aol.com]

Listers,

    It seems that i should have knocked on the laminated zebrano when last i
said the car was running in tip top shape.  Just yesterday i had it at the
carwash idleing and next thing i know, steam is billowing from under the hood
and the car is leaking coolant at an alarming rate.  Upon checking, i find
that the coolant is gushing out of the filler cap which is still secured to
the overfill tank.  Here's the caveat...i check the temperature gauge and
it's two ticks past halfway and the fan has not clicked on.  The fan usually
starts up about 1 or 2 ticks before halfway.  Further testing concludes the
fan will not click on in any circumstance....anyone have similar issues?
What should i be checking?  Thermostat?  Fuses? Relays? I dunno!

As always, many thanks,
Adam Chinchiolo
200q20v...sweating profusely with a bad case of heat stroke

PS: it was only 80 degrees...pretty mild for Stockton in May.