Hi, all.

I have an '82 aircooled Vanagon, and recently noticed a severe
screeching noise when I accelerate. The noise only occurs when the
throttle is opening and the engine is increasing in RPM. The sound
disappears at steady RPMs (no load) regardless of throttle position.
Slow, steady opening of the throttle without a load doesn't result in
the noise, but quickly opening the throttle or driving under a load
(accelerating) does.

So I'm wondering if it's associated with the distributor advance. I also
notice a distinct lack of power whenever the noise occurs, also like
what might happen if the normal ignition timing advance is interrupted.

My theory is that the advance mechanism has partially failed, and when
vacuum advance is applied, one of the mechanical advance weights is
rubbing against the distributor body or some other non-rotating part,
causing the noise. The screeching is quite loud, and seems proportional
to throttle opening, but only under load (high vacuum) conditions.

This is a California Vanagon with electronic ignition, so before I
attempt to disassemble the distributor, I thought I'd ask for opinions.

Thanks in advance!

...Dan

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