CGT fuel problem suddenly super rich then dead

[Stpndsmnn at aol.com]

Was driving around today and suddenly my car started to lose power terribly.
It would sputter and cough but not make enough power to move the car from a
stop and would hardly rev.  Really muddy idle and I had to keep my foot on
the throttle to keep it running.  Then suddenly it would be okay for a few
miles and then the problem would return.  I went through nearly a 1/4 tank in
about 15 mins!

What would cause this?  I am not a CIS guru, but I know how the system
basically works and don't have much in the way of test equipment aside from a
volt meter..

This is on an '83 CGT with a K-jet lambda system,  No CIS-e or eIII..

Please help
Thanks
Matt