EmilMD 8/4/2010Yes that is right, it could be a worn Lifters that causing the problem. The spring maybe weak or damage and it can return the valves into closed position. And it could be the Push rods that bends and cause a knocking or ticking noise to the engine.
It is the best thing to check the lifters and check the oil level through the dip stick that probably low oil. Low oil is one causing the knocking sound to the combustion. You have to change the oil if it is. Check your head gasket too along with the lifters to diagnose the problem further.
Replace any defective components and most important to remember always to change the oil base into the Maintenance Intervals of the car.