cold start: fires right up; warm start: sputters?

[wwwrpm]

Me again:

I had a random misfire code and replaced all 6 spark plugs, 6 ignition coils, cleaned the MAF sensor. The fuel pressure regulator isn't leaking gas into the vacuum tube. The fuel damper valve looks dry. The misfire code was cleared and hasn't come back. HOWEVER, it's giving me starting issues:

The symptoms:

Overnight, in the morning, when i start it cold it fires right up no problem.
When it's started after being driven for a while the starter motor spins and it takes like 1-5 seconds of me holding the key on start for it to finally turn over.Today I gave it a bit of gas to see if that would help it start up, and i'm not sure if that even helped. I do smell a gas smell in the engine bay, but i'm not sure where it's coming from or if this is a normal amount of gas smell.

At 311k miles the timing chain might be loose, and when hot it would be even more loose. I'm not in a position to replace the chain, but are there other culprits here that I might be able to fix to help this warm start issue?

[VStar650CL]

It's not unusual for crank or cam sensors to misbehave with temperature, cold or warm. They won't usually cause a code because once the engine starts, the added reluctor RPM increases the induced voltage and the sensor behaves normally.

[wwwrpm]

It's not unusual for crank or cam sensors to misbehave with temperature, cold or warm. They won't usually cause a code because once the engine starts, the added reluctor RPM increases the induced voltage and the sensor behaves normally.

i forgot to mention i did have DTC P1145 (cam sensor - bank 2), and replaced it.

hmm how could I test your theory?

[VStar650CL]

If it's the crank, next time it acts up, put a streaming scanner on it and look at the RPM while cranking. Almost all older Nissan ECM's get their RPM data exclusively from the crank, so if the sensor is glitching, it will show zero or "bouncy" behavior instead of the normal 200-or-so cranking RPM. You can't use the dash tach for it because most of them power off while cranking (and the needle is damped and won't respond quickly anyway).