Just purchased my first fixer up caddy an 88 brougham. I am allready lost, when the car is started you have to give it gas to get it to keep running. When you let off the gas if it does not die it idles very rough. If the car is given any throtle it smooths out and runslike a gem. I have allready changed the dist, plugs, and wires where do i need to look next, please help.