At 10:24 AM 4/5/2012, Richard Koerner wrote:
>putting things back on.  Do you need it?  I assume it's some kind of
>static-suppression device, but most modern radios

I think it's either AM radio spark noise suppression (along with the
resistive high voltage wires) or protection for the unshielded part
of the oxygen sensor lead, which is the only really sensitive thing
back there, as far as I can see.  I have real trouble thinking that
the ECU needs it, even though it's by the taillight on the 1.9s (and
my 2.1l has one, and its ECU is the other side of a steel wall).  But
clearly VW thought it was important, 'cause they spent a Deutschmark
(or whatever) on it.

If you take the cap off every couple years, how much trouble is it
really?  My only trouble really is forgetting to install it and
having to take the cap off again to put it on...

Yours,
David