Hot start-wont start

[James Miller]

Hello,

I'm having issues with the car starting once it is warm.
this is what is happening
1.the car starts fine after sitting since the day before
2. I drive 5 miles and stop and eat lunch
3. when I return after 45 min. the car didn't start on the first try but 
fired up on the second try (it was about 80 degrees and the car was in the 
sun)
4. I then stop next door to get gas and it wont start--the starter cranks 
and the engine almost catches but then dies.
5. with the car rolling-I pop the clutch and it hesitantly started
6. I then drove 15 miles and parked it in the shade. I tried to start it 
initially after parking it and it wouldn't go.
7. The car sat for more then an hour in the shade and started right up on 
the first try.
8. The car started with no problems this morning.
9. Then I stopped and parked in the sun at the bank after the car had been 
running for a 1/2 hour or so and it wont start. It's in a busy parking lot 
with little room so it is still sitting there. I plan to go back in a few 
hours when the engine has had time to cool down completely

A few years back the idle stabilizer valve was replaced--when that went it 
would catch but wouldn't stay at idle--this time the idle doesn't catch. A 
year and a 1/2 ago the starter brushes where dirty and it had trouble 
starting but after a little cleaning I've had no problems.

The car recently had a brass distributor gear installed. Could something 
have happened then? Am I silly to think that it might have something to do 
with sitting in the direct sun light?

I'm not in a position to do much until I get it home and so I put this out 
to the Audi minds--to get it off my mind as I wait in bewilder anticipation.

Thanks for time,
James Miller
91 200 tqa