After run mod S4

s4mark

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Hi. I have seen articles about changing a the after run mod thermostat switch to that of a blue type that operates at lower temperatures.

Has anyone fitted one of these as I read that it can only benefit the engine but would like to know if anyone off here has done the mod and if so is it recommended? Why did Audi not do it then?

Car is a B5 S4 (2000 year)

Thanks
 
i've done it on my S4. basically the temp switch as standard only operates at quite a high temp so the afterrun pump doesn't come on unless it's red hot and you've been thrashing it. i guess they set it like this as a safety feature as it only runs when it's absolutely neccessary. a big mistake in my opinion, do the mod and you gain the peace of mind knowing the pump will run most days cooling the system and preventing the oil burning away from the shafts in the turbos.
 
cheers mate gonna order one tomorrow from vagparts.:icon_thumright:
 
Well I have just completed the after run mod. It was an absolute nightmare though, just not budging first of all. Ended up shredding the plastic connector with my pliers after numerous attempts to remove with no sucess. Eventually after much soaking with oil and wiggling it eventually just popped out.:icon_thumright:
 
s4mark said:
Eventually after much soaking with oil and wiggling it eventually just popped out.:icon_thumright:

that's what she said..... :o.k:


slightly more on topic, this is the radiator thermostat? that keeps the fan running on the radiator?
 
its an after run pump switch that operates the system at a much lower temperature ensuring better cooling of the engine
 
it actually circulates the water in reverse around the cooling system after the engine is turned off, apparantly it's the best way to do it to prevent air pockets forming and already hot water trying to cool an even hotter turbo. just like a poor mans turbo timer, runs for anything up to 10 mins depending on how liberal you've been with your application of throttle and the ambient temperature