My 2003 Beetle overheated due to impeller disintergrated. Had it replaced at VW dealer. They stated no leaks in head gasket were detected. Drove 5 miles and it overheated again. They checked thermostat and all was good. They tested at high rpm "out back" and said all was good. I insisted on a road test and it overheated again. Another hour or 2 later, they said they now found a small leak and that the head could be warped, needing a $4,800 replacement. My question is when did the head warp ? My position is it warped during the ensuing overheating episodes at the dealer, not caused by the initial overheating. Anyone with thoughts on this ?