86 740T, 161K. Weird problem. In the morning, car cranks on first turn, engine runs so smooth you hardly know it is on. However, over the last week the last couple of times that I've driven it kind of hard (extended driving @ 65+ mph), after I let it cool down and turn it off, when I restart it within 2 hrs or so it has to be cranked twice to turn over, and it runs with a noticeable miss, which varies from slight to so bad the engine has shuddered, vibrates hard and sometimes cut out. I've done a super major tune up over the past two months (engine wires, distributor/cap/rotor/plugs). Fuel injectors/o-rings were also replaced). At first I felt like a vacuum line that might not be seated so that when things got hot and hectic under there air flow wasn't quite right, so I checked all of them and they all were secure and tight with no [obvious] leaks. Now I'm not quite sure where to proceed. Any thoughts?