Originally Posted by
Ebonycossie4x4
also if it was piston rings would the compression not be low?
it maybe a problem with the turbo then if its only on boost - has it been set up? what the AFR?
if its worn piston rings then yes it will show in a comp test, but if its worn oil rings then no they do not always show on a comp test
there's a difference between oil & piston rings