Everyone please repeat after me , THE TENSIONER FOR ALL 928 DOES NOT SELF ADJUST
-- it is mechanical -
a bolt pushes on a pin pushes on the tension arm pushes on the belt -- it does not self adjust , ratchet , click ,pop, When you tighten the bolt that is it .
The only " adjustment " that it makes is from about 30 slightly cup shaped washers which slightly change shape as they get hot . Before letting a " mechanic " touch your timing belt ask to see the factory tensioning tool , just say you want to see what a $400 tool looks like . If he does not have one .........do not let the " I have done so many that my fingers know how tight " --- Thank him for his time and find another mechanic -- that is the kind of guy who breaks bolts , snaps of the end off the camshaft , can not understand why the belt jumped etc. Once again , THE TENSIONER IS NOT A HYDRAULIC UNIT IT IS MECHANICAL if the tension is set incorrectly , it will stay incorrect . And yes I know the later models hold oil but it is not fed by the engine , you must pour it in , there is no hole in the block to feed oil to the tensioner . The oil assists the transfer of heat from the block to the tensioner and is used as a damper to control flutter of the arm .
Alex wrote ..... my
mechanic told me
that the tensioner automatically adjusts. He told me that the 1500mile retensioning was BS
Thirty years experience doing something incorrectly hardly makes one an
expert . He seems to know a lot about BS