how much for engine flush 80K miles. OIl change every 5000 miles

Who told you an 'engine flush' would clean the PCV system? PVC is plumbing pipe :)....PCV is Positive Crankcase Ventilation , in other words ,the vapors produced by your engine , that used to just be blown off into the atmosphere , are now sucked back into the intake and burned . When your dealer told you your PCV system or valve was clogged what did they try to sell you , besides installing a new PCV valve if equipped and or cleaning any hoses or tubes involved in the system?