So I have been dealing with this problem for about 5 months now. Went to every mechanic and they all say nothings wrong. When I start my car cold it hesitates but starts every time, but once i drive it around and let it sit for like 10 min it just cranks and cranks....can’t figure out what’s wrong. (Car is FBO Tune) tuner doesn’t know what’s wrong either.

car has 71k odo and one shop replaced cam shaft sensors and still nothing...I’m running 660cc injectors with OEM pump but tuner said that’s fine.

 

A vehicle not starting with a warm engine should have a pretty simple diagnosis?
Either your missing spark, fuel, or both and have a defective IPDM, ECM, or poor wiring harness connections that is preventing the vehicle from starting.
Drive to your nearest Infiniti dealer, pull into the service drive in, shut the vehicle off and let them tell you what is failing after they hook up the consult ll.
I would assume that neither you or your two so called mechanics have never read the FSM?

http://www.nicoclub.com/FSM/G35/Seda...5_Sedan/ec.pdf

Telcoman

 

I'm guessing a fuel pump, when it won't start but will crank are you getting anything on the tachometer? If you don't have a tach reading while cranking it's the crank position sensor but that's not usually a hot-start-fail item.

You will need a sandwich adapter for the passenger side fuel damper in order to check pressure, there is no service port on these engines unfortunately.

https://www.z1motorsports.com/z1-pro...rt-p-9160.html

If you're not getting spark then it's usually either the crank or cam sensors, test for spark just like you would normally on any other vehicle.