Task: Question Answering
Input (English): Process:  -Fuel mixes with air -Mix gets inducted into cylinder -Piston compresses the mix -Spark plug emits a spark that ignites it causing combustion -Combustion gases expand -Pushes piston during power stroke -Exhaust valve opens to vent exhaust out tail pipe.
 Question: What is the effect of the engine valves do not get stuck on the piston will not be pushed during the power stroke.?
Output (English): against