Alfa Romeo Repair: Alfa 156 2.0 TS hot starting problem, alfa 156, pressure gauge

Question
Hi Stephen, my 2000 model Alfa 156 has developed a hot starting problem. The car starts perfectly when cold, and idles well.  On attempting a hot restart, the engine fails to start.  When left for 20 minutes, it'll start 1st time. Breakdown mechanic reckons its a the crank speed sensor thats developing an open circuit when hot. Any other ideas?

Answer
This actually sounds like a failed check valve in the fuel pump. To test, a pressure gauge is needed.  After shutdown the system should gradually loose pressure for at least a half hour.

At anyrate it is necessary to determine if the problem is igniton or fuel before parts are replaced. But, the odds are it is related to the fuel pump. The pump can fail anytime after 90k miles.