Stan Wilder wrote:

> Please explain "Just make sure your knock sensor is working!  ".
> I've never heard of this before.
> I've got an 83 Aircooled 1970 cc FI, so it might not even apply to me.
>
> Stan Wilder
> 83 Westfalia Air Cooled

You're right.  It's a more recent invention, never used in factory vanagon
engines that I know of.  Earliest I've seen is in an 88 Jetta, but I don't
know the whole history.
  In engines where the ignition timing is controlled by the ECU, it can
advance the timing until it senses the pinging from ignition too
early/octane too low. It then retards the spark just far enough to stop
the knock.  The idea is to prevent damage from pre ignition and still let
the engine take advantage of the extra power possible if you use high
octane gas.  Sounds good, maybe it even works.

Larry A.