Daughters 95 Caviler (160K Km) started burning an extra liter of oil between 5000 Km oil changes and the check engine light started coming on.
After having all the proper service checks required all along. One of the engine servicing guys told my wife that it was the PCV and I think it was. The light is gone and it's only now to see if the car makes the 5000 without needing to add oil.