Question

which of the following is a function of the positive crankcase ventilation (pcv) system?

a. it burns fuel vapors from the charcoal canister.
b. it directs blowby gases and vapors back into the intake manifold.
c. if prevents exhaust gases from entering into the engine.
d. it ensures that the ventilation capacity is less than the amount of blowby.

Explanation:

The PCV (Positive Crankcase Ventilation) system takes blowby gases (unburned fuel - air mixture and combustion by - products that leak past the piston rings into the crankcase) and redirects them back into the intake manifold. This allows these gases to be burned in the combustion process, reducing emissions.

• Option a: Burning fuel vapors from the charcoal canister is part of the evaporative emissions control system, not the PCV system.
• Option c: Preventing exhaust gases from entering the engine is not the function of the PCV system. The PCV system deals with crankcase gases.
• Option d: The ventilation capacity of the PCV system should be sufficient to handle the blowby, not less.

Answer:

B. It directs blowby gases and vapors back into the intake manifold.