Clicking when accelerating. smoke comes out exhaust when pressing down on the gas peddle in park

so i was driving, everything was fine, than about ten minutes later, my car starting making a clicking noise when i hit the gas, i got to a stop light, shut off my car, turned it back on, and it still did it. it would take a few seconds for the car to react when i hit the gas. so i got to my bank because i had to file a dispute, left my car shut off, than went back out, tried to start it, and it would not start at all. now, when i tried starting it, it smelled like something was burning. I have never smelled burnt oil or coolant, so i do not know if it was that. please help. its in the shop right now. they have checked ICM, spark plugs, battery, air filter, oil change. is there anything else we are missing? he has checked other stuff too, i just forgot what it was.