4KQ Smog Problems-Update, still stumped

[Huw Powell]

> > Ign timing is set at idle... and I *think* that vac. adv. thing does its
> > work *at idle* if you follow where the "vacuum" comes from.  So your
> > timing is really not where it should be.
>
> Actually the vac advance works right off idle. At idle there is no advance,
> crack the throttle open and you have vac advance. If you look at a throttle
> body, the port for the vac advance line is in a place so that at idle, it is
> on the outside of the throttle butterfly and as soon as the throttle opens,
> it is on the engine (vacuum) side of the throttle body.

Whoops, you are so right.  I never noticed that tiny hole before, I
always thought the vac port simply tapped into the idle screw bypass air
thingie.  cool.  that makes a lot more sense now...

--
Huw Powell

http://www.humanspeakers.com/audi/

http://www.humanthoughts.org/