warm starting 200tq

[FLIPMONDS@aol.com]

Any listers have this symptom?  When my 200 is warm and has sat for more than 
5 minutes it fails to start right up again.  I crank the engine and crank 
some more.....finally I put the pedal to the floor and crank some more( how 
poetic!)  In any case after cranking at 10 second intervals for about 20 times, the 
engine finally fires up.  My mechanic has suggested that there is carbon 
build up around the valves and injectors giving less than optimal air fuel mixture 
for startup.  Why only when warm though?  Any remedies short of a valve job?
Thanks 
phillip edmonds