Hard starting when engine and ambient temperature is hot.

[George Harris]

The patient is an '89 Audi 200 automatic non Quattro.

I have been unable to understand accessing the archives, so I appeal to 
the listers:

The patient runs strongly and smoothly once it is started. When cold it 
starts easily. It starts easily with a few seconds of turning over if 
started immediately after being turned off.

The problem occurs when the vehicle sits for up to an hour while it is 
hot outside. It has to turn over for a longer period of time as the wait 
lengthens.

We have a second Audi and many parts have been switched with no 
solution, and all tune up parts have been replaced: spark plugs, 
hi-tension leads, distributor cap, rotor.

I would appreciate any help in diagnosing this problem.

Cheers
George