[200q20v] Knock Sensor & Oil Cooler Info

[Jeff.Bernstein at pneumaticscale.com]

I had noticed that over the last few months I wasn't getting as much boost
and the boost was coming on slower.  I finally saw a code referring to the
#1 knock sensor.  I  looked at the sensor and found that all the outer
plastic cable shielding was cracked and was disintegrating quickly.  I
replaced both knock sensors since the #2 sensor was starting to disintegrate
also.  I now have full boost and it comes on faster also.

As I was working on the car I also noticed a large leaf was blocking part of
the oil cooler.  I decided that in order to get the leaf out I had to remove
the ducting in front of the oil cooler.  Upon removal it became obvious that
the cooler was almost completely clogged with dirt that had slowly
accumulated over the years.  I could hardly see any light though the cooler
and the dirt was baked on especially the bottom half of the cooler.  I
disconnected the cooler from the frame and lowered it into a bucket of
water, leaving the lines attached, and soaked it for 24 hours.  I then used
an air compressor to blow the small gravel and sand out of the cooler which
took almost an hour of work to get the majority of the dirt out of it.  I
had noticed that it seemed like the oil temperature was hotter than it used
to be but it was going up over the years at a very slow rate due to the
gradual build-up of dirt. 

I took the car out for a test drive after fixing all these things and was
pleasantly surprised to find that the oil temperature was noticeably cooler
even though I was making a lot more boost.  I would suggest that anyone with
a high mileage car should take some time to check these two items.  Very
rewarding weekend project.

You can see my car at a web sight that my son made for our various Audi cars
at http://www.bernsteincars.8m.com/.

Jeff Bernstein