Wheel Speed Sensor Grunge!

[Dan Hamren <dan@magnitude-electronics.com>]

OK So months after you guys pointed out that the noise my brakes were
making were because the wheel speed sensors were too far away from the
sensor rotor, I bought some caps.  The caps, are designed to put the
sensor at the right distance.  Carlsen Delivers the parts I put them
in.  Pull out the sensors, and the Grunge...... Ohh the Grunge.  Ok no
biggie, even though my mechanic said that he pulled them and cleaned
them (LIAR).  Ok so I put them in...Left side, then Right.  Time to test
drive.  WHAOOo.  The Abs goes on immidiatly, and then the computer
automatically shuts it off.  I drive a little down the street then hit
the abs off button to get it working again Touch the brakes boom....abs
starts working, abs off light comes on again.
Should I take them out clean them and tap them in with a mallet?  Am I
still too far away?  should I skip the caps and just adjust them until
they work properly?
I think there is a bunch of grunge on the speed sensor rotor.
TIA   Dan Hamren     1987 Audi 5000 cs quattro wagon   145,000 miles
Just getting warmed up!  Chip and spring comming soon!