what does a pcv valve control?

Answer 1

Positive Crankcase Ventilation valve is an emissions control device that routes unburned crankcase blowby gases back into the intake manifold where they can be reburned. The PCV system is one of the oldest emission control devices, and also one of the most beneficial. Besides totally eliminating crankcase emissions as a source of air pollution, the constant recirculation of air through the crankcase helps remove moisture which otherwise would cause sludge to form. Thus the PCV valve extends the life of the oil and engine. The PCV valve requires little maintenance. The valve and filter should be replaced somewhere around 30,000 to 50,000 miles (see the vehicle owners manual for service intervals).

Answer 2

To understand what it controls you need to know what a PCV valve is. PCV stand for Positive Crankcase Ventilation. It controls how much air passes in to the crankcase of the motor. With out ventilation the pressure would blow seals out on the bottom half of the motor. It also helps relieve other gases from the crankcase.

Answer 3

PCV (Positive Crankcase Ventilation) valve is the cheapest to buy. It cost less than $10 at Kragen (auto parts store).

Copy and Paste from http://www.about.com
The Positive Crankcase Ventilation valve is an emissions control device that routes unburned crankcase blowby gases back into the intake manifold where they can be reburned.

Answer 4

Positive crankcase emmissions valve .It is a one way valve that allows the emissions from a car engines crankcase to be burnt in the ignition chamber of the engine instead of venting to atmosphere.

Answer 5

Is this a trick question --- the real function of a PVC valve is to let hot air out of the engine and prohibit cold air from entering the engine-- as cold air will cause the pistons and block to have minute cracks and it will also cause burned or broken valves ----the idea is to keep the engine at an even hot and factory specified temperature...

Answer 6

PVC stands for, positive crankcase vent. It controls the oil and fumes in the crankcase, recirculating them to the intake manifold to be burned along with fuel, this keeps the environment clean, and keeps you from smelling the fumes.

Answer 7

It controls crank case ventilation pressures that develop when the crank is spinning at all rpms. And thus the fumes, and oil spray that is produced is tranferred into the intake.