mine has exactly the same problem as yours its a 95 ady 8 valve, mine has new leads plugs cap et6c etc i have also cleaned the throttle body, and no air leaks!, i am due to replace the crank sensor as mine has a crack in the cable and occasionally say once a week will start but cut out immediately 3 or 4 times, so will update you on results of that however i suspect it's the road speed sensor so thats my next thing to change, i do also suspect that it could be the iat sensor on the airbox.