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Hard start when hot- leaking injector?

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Hi gang. 2005 x3, 2.5, 173K. Runs and idles just fine but when restarting when hot, excessive cranking required, and raw fuel smell when it finally starts. I'm thinking leaking injector(s), not necessarily bad o-rings. Any suggestions for determining which squirter it may be? Me: ASE tech in previous life....Thanks, Aloha, Steve.
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Perform leak-down test of fuel pressure; however, if the injector was weeping and bleeding down, you'd also see extra cranking on a cold start.
My 04 M54-powered E53 had a leaky injector. Apparently there was a bad batch of Bosch injectors from that era. The symptom was hard restart only when warm. Overnight restart was always normal. I guess the extra fuel had time to evaporate enough overnight or the cold engine's natural desire for richer mixture upon startup made it a non-issue. I replaced all the injectors since they were all vulnerable. Looking at the codes, I was able to determine one was newer, so had been replaced at some point. I kept that one for a spare.

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