Can only a dealer do a leakdown test with special equipment? Also, if you put (I'm guessing compressed air) into the cylinders, couldn't that theoretically make a little problem worse by exerting all that pressure on let's say the rings or whatnot? I have no idea...that's why I'm asking!
'86 420SE Euro
904 Midnight Blue, Gray Velour
Dad bought it new, now I own it.
"A Mercedes-Benz is like a fine wine, it only gets better with age."