CAr has 211,000 miles, Last weekend car sputtered and quit. It had no power and would not start. Thought mabe a fuel problem, put 93 and Lucas "real" fuel treatment in tank. This allowed it to idle, but when applying pressure to gas pedal it would cut out and a puff of smoke would come out on the air intake. Thought TPS didnt work. Tried spark plugs Bosch +4, plug wires, cap, rotor and a coil pack. This made it start and run fine............BUT there still is a miss under load, i can get it to do it constantly when i apply pressure to the brakes and floor the car. Lastly i have replaced the fuel filter. Please help if you can, i am lost now and sensors are expensive.