1990 200 TQ Overheat problem

[George Tur]

On Sunday 07 August 2005 10:50 pm, KWSTURTZ wrote:
> My Audi Quarto 200 overheats and the fan does not come on to cool until
> 2 late(3/4 of temp gauge)  and does not stay on long enough to cool it
> bellow boiling i drive on freeway i can keep it cool until i get into a
> traffic jam , Come to find out if i turn on heater THEN (no mater if
> overheat or not )the  engine / radiator cooling fan comes on and it runs
> like a champ 1/4 -1/3  on the temp gage at all times.  So what i think i
> need to know is how to make the fan run properly without having to turn
> on the heater.  Work done on  car in last 120 days is  new head, new
> water pump,   new  radiator and  new cooling fan. All reply's greatly
> appreciated.
>
******************
I'm not sure about this model audi, but I do know that for the earlier 87 5ktq 
and the later 91 V8 the fan speeds are controlled through a resistor pack and 
a set of relays. It might be that the resistor pack has gone bad and it only 
allows current flow through for the highest fan speed, or maybe the low and 
mid speed fan relays are toast. Take a look at this link for the fan trouble 
shooting procedures at Scott Mockry's (spelling??) web site:

 http://www.sjmautotechnik.com/trouble_shooting/cooling.html#fan

Good luck

George Tur
91 V8