1994 Chevy cavalier 2.2 liter shutting down at stops, lost of power around 40mph and 10 miles later. Tried too restart starts and as soon as I put in gear it shuts off. Before this trouble and 10 mile trip I replace all spark plugs and wires, cleaned intake & replaced PVC valve also treated fuel with sea foam engine cleaner as well as filled up on 93 octane fuel. Air filter last change when oil was changed 3000 miles ago. Vehicle has 134000 miles on engine last major tune up of all gaskets and water pump & thermostat done at 104,000 miles. I tested each spark plug wires for arcing & I had voltage from ignition coils (all 4). Can you point me in the right direction?