I have a 94 940 with 175,000 miles. I'm experiencing a flutter or hesitation when I'm cruising, 55mph little throttle. I've cleaned the throttle body and replaced the flame trap, replaced air filter. When I use an injector cleaner I don't notice it so much. Im going to try using a better grade fuel, currently use Wal-Mart, cheapest. also thought maybe oil in distributor or maybe new plugs. Any suggestions?