The PCV valve on 2.0L and 2.5L engines requires special attention: the valve will break while it is being removed and cannot be reinstalled hence requiring a new one as well as the hose. First of all one have to remove the engine cover, secondly one have to unscrew the nut which fastens the end of the PCV hose assembly to the intake system and take out the fitting. Check the condition of the O-ring and if found in bad state replace it. For engines 2.0L and 2.5L unscrew the PCV valve from the valve cover, the cover would split in two; make sure to take all parts from the location of the valve cover. Tighten the new PCV valve into the valve cover using your hand's force until the valve securely sets down. In the new engines the air partitioned valves are in the value cover; 1.5L & 2.5L have two valves while 2.0L have three. When the engine cover is detached search for the fresh air valve scoops. In the fresh air valves of 2.0L and 2.5L engines, remove the quick-connect fittings and the hose assembly from the fresh air hoses while in 1.5L engines, trim the hoses ends in order to allow easy removal of the valve nipples. In some models, however the fresh air hose assembly may be held by a bolt. Pull the fresh air valve from the valve cover, taking care to cut a slot in the tamper-proof fastener, if the car is a 1.5L model. Check the condition of the O-ring and replace it if necessary, then disconnect the fresh air hose from the air intake system, but keep its end connected to the intake air duct if you are working on the 1.5L power plant. In a case where the hose assembly requires replacement, then one is supposed to sever the hose fitting from the duct fitting. As it was done in the removal, installation proceeds in the reverse order.