To increase the efficiency of the PCV system, to converge the hoses of the PCV and to check the state of the PCV valve according to the schedule of regular maintenance. Find the PCV valve which is usually positioned on the cover bust near the brake booster for 4.0L pushrod V6 intakes while for 5.0L VB intake it is positioned at the back of the manifold. To test the valve, one is supposed to withdraw it from the grommet and vibrate it; if it does not vibrate then the valve is stuck and needs to be replaced, in the contrary, if it vibrates, it needs to be reinstalled. Switch on the engine, let the vehicle run for some time and then remove the PCV hose; if vacuum is experienced, then PCV valve system is okay. If no vacuum is sensed, inspect for leakage at the oil filler cap, hoses or at the valve cover gasket since they may have a connection with the problems of the PCV valve. Pull out the valve in an upward motion and check the area of the rubber grommet for crack lines; if evident, the rubber grommet must be changed. Should the valve be blocked then the hose is blocked too, so it has to be removed and washed with solvent. After washing inspect the hose for any damages and make sure the hose seat well on the fittings respectively. If needed, replace the PCV valve; that the elbow (if installed) is located is not included with the unit, however has to be carried over from the original. Subsequently, if a new elbow is bought, one has to immerse it in warm water for upto an hour to make installation without breaking it possible. Last, put back the clean PCV system hose and make sure that the PCV valve and the hose are well fixed.