Hello Community and Scotty,

I have been watching Scotty's Youtube videos for years and I am in need of some help.  I am not a mechanic, so how I describe my issue may not be how a mechanic does, so forgive me.

I have an 01 Nissan Frontier, V6 automatic with about 250k miles.  About a year ago, truck started "surging" - erratic and excessive engine RPMs over required by the gear and speed.  This accrued at idle or at any speed up to 75 mph on the highway.  The occurrences of the surging was also erratic - it would be present at startup on a cold engine one day, or at 30 mph after engine was warm (when not presenting earlier in the drive) on another day, or even after 3 hours of highway driving at highway speed on another day.  Some days the issue never presented itself.  Local Nissan dealership said it was presenting "3rd gear ratio" issue, which is a death nail for the transmission per them.

A few weeks ago, I was driving around town and after a few stops (start/ stop of the vehicle), it died on me at a red light.  It would not turn over.

I had it brought to a local Nissan dealership - where I have had all my major maintenance performed.  Upon startup it ran smooth and took 45 mins of the truck running to for it to present any issue to the mechanic.  It apparently started running very rough.  Diagnostic tools show the "air being on the low end" and the engine RPMs (from the scanner) not matching the physical engine RPMs for a portion of the time.  No codes were present (not even the "3rd gear ratio" as mention before) .  The mechanic took some short drives with no issue.   

I am not sure if these events are related, but it seemed like a good idea to let you know the recent history, which I have tried to summarize.    

I have kept up with oil changes and all major maintenance that presented itself.  Truck has never really given me any issues, outside of a new transmission that was required at 200k. 

Thanks for any help you can provide.