Bizarre Hot starting problem on 164

[Carl Prochilo <Carl_Prochilo@domain.elided>]

I've checked Tech notes and found no mention of the problem I am
having.  My Alfa mechanic is baffled as well, but he is still looking
for an answer to my problem.  Let me explain, and if you've experience
this problem and know of a cure, please e-mail me privately with a
response.
After driving the car and having it reach normal operating temperature,
then stopping the car for about 5 minutes and then attempting to restart
the car, it sometimes will not start.  Opening the fuel filler cap has
no effect.  However, opening the oil filler cap on the engine will
always allow the engine to re-fire!!!   This is maddening and makes the
car unpleasurable to drive.  Today alone I got stuck twice, the second
in the middle of a crowded intersection, and let me tell you it is no
fun to turn your hazard lights on, pull up the parking  brake, open the
hood and get out to remove the oil filler cap while everyone watches you
work on your Italian car.
Before you answer, I'll mention that the Fred DiMatteo procedure to
replace the 3 inch braided fuel line in the gas tank has been recently
performed.

Thanks for listening,
Carl Prochilo
1991 164B

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