quattro20v

<center><img src="http://pictureposter.audiworld.com/52091/switch004.jpg"></center><p>I figured out a way to make the after-run fan (and coolant pump) come on more frequently. I purchased a temperature switch from a 1990 90q20v (p/n 034 919 369 A) for $25 which measures underhood temperature (not coolant temp) and is set to turn on at 85 celcius and off at 80 celcius. The switch is threaded with a 10 mm thread and I picked up a used mounting bracket from a 1990-1992 VW Passat 16V and mounted it along with the switch on the valve cover using the rear allen bolt on the passenger side. I extended the wires that feed the stock switch and ran it to the new switch.

Now the after-run fan and pump comes on about 80% of the time. I tried mounting the switch on the driver's side, but it did not get hot enough to trigger the switch. Since the switch is just above the downpipe, it will see the highest temperature.

FYI, the stock switch doesn't come on until the coolant gets to 110 celcius which takes quite a lot.

Sean D.

cpayne

Good work..pls post part numbers and procedure if you have a chance..thx

quattro20v

If you have specific questions, I'd be happy to answer them.

tpierce

that is what i was going to do when I got around to getting one, seeing as the normal operationg temp of the car is ~85C. Plus, i doubt it stays on very long over there as the fan might be pushing cooler air over it.

quattro20v

The new switch only measure air temp. I doubt it would fit and seal properly like the stock switch.

Surprisingly, it stays on for 5-10 min, 10 min maximum which is the maximum time allowed by the timer relay.

bar1

You need similar behaviour for the new swith! For insurance..