Diesiling?

My 87 cutlass supreme (obviously) shakes and shit when i turn it off, its like those old cartoons. Well my freinds tell me its deisiling, what do they mean by that? How can i fix it?
Thanx
Jessica

Is the car idled high because that was the problem with mine the idle was set too high and I lowered the idle and that fixed it.

How do I check? It doiesnt make any wierd noises when i am stopped or anything... sometimes in the morning when its cold i turn the thing on and it shakes uncontrollably, i feel like im on a roller coaster ride.

It sounds like the choke is staying close which would cause it to do that. when this happens is it smoking black out the exhsaust. If it is then your might need to check the vacum on the choke pull off if it has vacum then you might need to replace it. This is on the side of the carburetor. Hope this helps and the idle screw is on the divers side of the carb.

Is this a fuel injector or carburetor type fuel system?