[s-cars] Re: After Run Pump - Can it come on at a lower temperature?

[William Noland]

The after run pump is pretty quiet. If you look at the radiator expansion tank after shutdown, you should be able to see coolant squirting into the tank, as the pump works. As for installing a lower temp switch, I shouldn't hurt anything. The after runpump is there to prevent the oil in the turbo from coking up. This only happens at very high temps. You
seldom hear of turbo failures on the list, so it must be doing its job, as intended by Hans and Fritz.

Bill Noland


> The auxillary pump (and fan) is apparently set to run when the engine is
> turned off and the coolant temperature reaches 110C and shuts off at
> 97C. I've never witnessed this happening as 110C is pretty high. Has
> anyone tried replacing the thermo switch as per the S4tt (see link) to
> come on at a lower temperature? This seems like a good idea to me.
> Anyone have part numbers?
>
> http://forums.audiworld.com/s4/msgs/1629709.phtml