2004 g35, won’t restart after running a while; car must cool off before restarting. Sometimes it turns several times before starting or restarting, as well. Feels like an air and fuel mixture issue.
We’ve changed:
fuel pump
cam and crankshaft sensors
spark plugs
mass air flow cleaner
LKQ IPDM module
and general tuning..
any ideas?

 

How confident are you in the lkq ipdm? I know how they store their cars and the ipdm was probably in many rain storms

 

I would first check that you are getting spark while you experience the trouble starting. Maybe even have the starter rebuilt for good measure

 

Thanks for responding:
The engine is now restarting more consistently since changing this particular module, although it turns several times before starting. What kind of adjustment (air/gas intake) if any might I try to get it to start on the first turn.

 

Can try the idle air volume reset. And the ECU reset. I'd be looking more into a failing cam or crankshaft position sensor. Did you use oem sensors?