I personally would not rule out carb problems. Back in those days (82 & later) the automakers were facing more stringent emissions, and one result was carburetor complexity. The manufacturers complained that fuel with ethanol in it was hard on some of the internal non-metallic parts of carburetors; like the plastic tips on the electrically controlled valves, the one for the idle cutoff, and the one for the float vent. This was enough of a problem with the Mikuni carb on my 87 Dodge minivan, that the vehicle got its first replacement carb while still under makers warranty, and was on its 3rd replacement professionally rebuilt carb (nationalcarburetors(dot)com) as of two years ago - when I gave up chasing problems. Now that vehicle is just my lockable tool-box. The idle circuit fuel shutoff is likely a solenoid driven valve, that shuts off fuel when the ignition is off - so the engine doesnt keep doing what was called 'dieseling', i.e. not shutting off, but coughing and stumbling briefly. With my minivan, I could always get it to start by dribbling a little fuel into the carb (either throat), but it would only run till that much fuel was used. Sometimes I could get it to work by rapping the body of the carb with a ballpeen hammer. There wasnt any good way to tell if the fuel cutoff valve was opening up again, or if the other two electrically controlled valves were working; the float bowl vent valve, and a fuel metering valve.