I just picked up an '86 Scirocco 16v.  A few weeks ago it would start
with a little luck, now it just turns over but won't catch.  If I let
it sit a day or so it will run for a few seconds on the first try,
then stall and not catch again.

The only thing that happened in between was I took apart the air
intake/fuel injection box for cleaning.

The battery is charged, and the plugs spark when I pull them out and
test them to a ground. I can hear the fuel pump activate when I put
the key in and turn it, before cranking it.

Please bear with my beginner's knowledge! Where should I look next?

~ matt