with the mileage you have on this car, I would check chain stretch.. you said use little oil, when you start the engine are there puffs of blue smoke at the tail pipe, if so valve stem seals need replacing.. If you hear a slapping sound when starting the engine shut it down!!! You need to replace the chain, tensioner, along with upper guides.. the guide on the left side of the engine is the one that is varnable to breakage, an damage your engine by breaking off an lodging inself into the cam gear,those blowing the engine..
Don't full with this if you hear chain slap, it wipes out the valves which requires a valve job $$$$
Bob