Has anyone had any luck in diagnosing this issue? I have a 2013 sport with Stillen CAI and Exhaust. I've been having the exact same issue and had the issue pop up this morning from a cold start

I guess this issue has not been resolved yet, I have a 2009 370 sports package with just k&n filters in the stock location with fast intentions long tube headers and exhaust. I still get this issue from time to time , sometimes it's when it's cold sometimes it's fully warmed up. Have any of the performance shops such as fast intentions come across this before and have fixed it?

I've had the same problem with my 2014 Nismo with Stillen cold air intake. Intermittent safe mode on start-up. Returns to normal after shut-down for 15-20 seconds. Dealer has been working on it for a week now, still no answer. Factory technician was in and also looked at it--no joy. Replacing MAFs because they failed, but techs don't believe they are the cause.

Follow-up
 

After 17 shop hours of diagnosis, including reinstalling the OEM intake, inspecting the IVT sprocket, pulling the tranny to check the flywheel, replacing the positive battery cable, and other tests, the factory tech has identified the ECM as the culprit. New one being installed tomorrow, under warranty because the problem was documented in my dealer service history before the bumper to bumper warranty expired. Keeping my fingers crossed.

back to the drawing board...
 

Now 23 hours of diagnosis & still no joy. ECM didn't cure it, so the factory rep now authorized them to try the IVT sprockets (the local tech suggested them as the culprit early on, but the factory wouldn't authorize trying it under warranty until they ruled out everything else, up to this point, first). Local tech looking kinda smug right about now. Will be intolerable if this works. Stay tuned...

Strike 4
 

IVT sprocket not it. Factory tech line rep flying out to inspect...

Send me the logs I can try to get you answer.

just got my car back
 

After five weeks of diagnosis, both dealer and factory tech believe everything is now operating nominally. consensus appears to be sticking IVT sprocket(s) were, in fact, the culprit. ended up getting a new ECM, IVT sprockets, timing chain (all under warranty as part of diagnosing the problem). Kudos to dealership for not giving up and (fingers crossed) getting to the bottom of it.

Impressive. Thanks for following up along the way :tiphat:

I fixed this problem by giving the throttle bodies a thorough cleaning.