I have a 2003 G35 Coupe. The engine usually runs fine but does have one existing issue I just live with. When I turn the key to start the car the engine doesn't start quickly and stay on without me pushing the gas pedal, otherwise it would start and then quickly the RPM drops and the engine dies. Once started, the standing idle level seems low to me and there has been an occasion or two where the RPM just drops enough during idle and the engine dies. So I'm not sure what that problem is there is a second more serious problem, (maybe related).
The real major issue is that my engine is exhibiting a strange behavior where the engine stalls while I'm driving and usually comes right back on within a second or two. This has happened about 4 - 5 times over the last 4-5 years. It always occurs one time and then doesn't happen again for months. But it just happened a couple days ago. I'm driving 70 mph on the freeway, the engine completely shuts down, tach instantly drops from 3000 to zero, then the needle resumes back as the engine turns on again within seconds. When the engine stalls, the dashboard lights all flash on (they go back off as the engine resumes), I believe my steering is affected and maybe even the brakes although it happens so fast and I'm usually panicking it's hard to remember exactly. Another thing is that when this has happened in the past and I was stationary (at a stop light) and the engine dies, when I turn the key to start the engine, it doesn't start very easily. Currently after the latest episode the Check Engine Light remained on, but the car is otherwise returned to driving like usual. Previous episodes didn't leave the Engine light on ever so that is new.

Does anyone have any ideas? I am meeting with a friend to diagnose the engine light code in a few days so that may reveal something. I'm not a mechanic but it appears to somehow be electrical perhaps? Again, any thoughts are appreciated.

 

The ECM is telling you what the problem is with that CEL. Get it on an OBD2 scanner to find out.

 

Using the OBD2 scanner, I got a code of P0335 (Crankshaft Position Sensor A Circuit). Anybody have anything to add?

 

Buy a Hitachi or oem sensor, replace it