[s-cars] Replacing Spark Plugs after Compression Test

[Dave Forgie]

I won't deny that the non-torque wrench, re-used plug/crush washer scenario isn't real.  I am just looking for the reason that some people (several recently over on AudiDoodiWorld) have blown plugs out of their heads.  If everyone installed their new plugs to 22 lb ft and checked them periodically (once a month or at least at every oil change), then why do plugs decide they want to vacate the premisses?  There has to be a logical reason.  I was going to the "crush washer as pretensioner spring" theory.  Obviously, the flattened crush washer and a tonne (but undetermined amount) of torque can also work.

Dave F.