The positive crankcase ventilation or PCV valve plays an important role in the pollution-control system on the Jeep Liberty. The PCV valve vents positive pressure inside the engine (called the crankcase) back into the engine air intake to make sure no unburned hydrocarbons from the crankcase are vented into the atmosphere. Making sure the PCV valve is operating correctly ensures that your Jeep Liberty is working efficiently.
Find the PCV valve sticking out from the oil-fill tube with a black rubber vacuum hose coming from it.
Push the PCV valve in and twist it to the left, then pull straight out to remove the old PCV valve.
Remove the rubber vacuum hose from the PCV valve by pulling it straight off the old valve. Discard the old PCV valve.
Install the new PCV valve into the side of the oil-fill tube by pressing it in and twisting to the right until it is tight.
Reattach the vacuum tube onto the new PCV valve by pushing it straight on.
