tollboothwilley wrote:If you are under warranty take it to the dealer. It sounds like a sensor issue.
Warranty is 4 yr/60K miles bumper-bumper5yr/70K miles for powertrain
My guess is either
1> Battery cables are coming loose at one end or another and cutting off supply to the battery
2> wire inside dash or engine compartment is loose and shorts out killing the engine?
Either way that car is not safe to drive someone is going to hit you when it looses power and you stop and they don't. Even if you have to pay out of pocket get it fixed! Its not an issue that is going to be diagnosed over the internet. It needs to be looked at by a Infiniti Tech, it may not even be something that you can fix.
My hemi ram did the exact same thing when it had less then 50 miles on it. ECU was reflashed and it never did it again