what do valves do in a car?

Answer 1

i own a repair shop,and all they do is open up,and let the fuel in,and then open back up,and let the exhaust out of it,this happens many times per minute,and continues to happen all the time ,good luck i hope this help,s.

Answer 2

not one person explained valves worth a crap.
let me try we will start with the four strokes of a four cycle engine
1. Intake
2. Compression
3. Combustion (Power)
4. Exhaust
on most engines u have at least two valves per number of cylinders and can have as many as 5 valves per cylinder for now could be more later. each valve does one of two things its either an intake valve or an exhaust valve. meaning when the cycle starts on a four cylinder engine the piston starts at top dead center or (TDC). the piston moves down on its first stroke the intake valve (by way of the cam shaft lobes) opens letting fuel and air mixture into then engine as the piston moves down and the intake valve is open it creates a vacuum that is how the intake stroke works. then the intake valve(s) closes and the piston at bottom dead center or (BDC) starts back up the cylinder for compression. it compresses the fuel and air mixture. note no valves are open, next the combustion stroke occurs with the piston at TDC again the spark plug ignites the fuel air mixture forcing the piston down due to the expansion of the gases in the combustion chamber. the piston reaches BDC and the exhaust valve(s) opens by way of the cam shaft lobes. the piston then comes back up to TDC forcing the exhaust gases or (burned air fuel mixture) out of the combustion chamber on its way up then as fast as it closes the intake valve opens and the process repeates. HOPE THIS HELPS. valve are controlled by the cam shaft which turns at half the speed of the crank shaft. so if ur engine is running 1600 rpm the cam shaft is moving 800 rpm

Answer 3

The intake valve allows the fuel air mixture to enter the engines cylinder where it is ignited by the spark plug which causes the piston and it's connecting rod to be forced down in the cylinder which in turn causes the crankshaft to rotate sending power to the transmission/transaxle which in turn drives the vehicle.The exhaust valve allows the engines burnt fuel air mixture to pass out of the cylinder and into the exhaust system and eventually out to the muffler and to the atmosphere.The "egr valve" exhaust recirculation valve allows a certain amount of exhaust gases to be sent back through the intake manifold to help the engine come up to full operating temperature quicker.The "pcv valve" positive crankcase ventilation valve allows excess crankcase gases to be recirculated back through the engine so that they can be burned.

Answer 4

the intake valves open to bring in fuel and air into the cylinder then close. after the cylinder fires the exhaust valve opens to let the exhaust gasses pass out of the cylinder. as long as the engine is running its a continous operation of the valves.

Answer 5

You have usally two valves one is to bring your air and fuel mixture into the cylinder where your piston is and the it closes and boom your spark plug ignights that mixture and blows that piston down causing the engine to turn when the cylinder comes back (up) around the other vale opens and exhast out the talil pipe.
Intake ,Compresion, Power, Exhast = four strokes ehh.

Answer 6

,The valves control the compression in the engine as the intake opens and allows fuel to enter then closes to compression and fire, the exhaust valve opens to release the spent gasses

Answer 7

To put it simply thy let fuel in and let the exhaust fuems out

Answer 8

Open & close.