Crank up the motor , feed some ATF down the PCV hose to the
intake manifold, 1 to 2 pints some times 3 , will clean out that motor, There is a company called Seafoam, Part number 4032507 that will clean out the top end of these motors. ,,20,000 hours on some of these Mazda motors is not uncommon.
This is ONLY to be used to report flooding, spam, advertising and problematic (harassing, abusive or crude) posts.