Ahhh, piece of shit Nissans....Why doesn't this company go out of business?
Anyways, check your FPR, see if your getting correct fuel pressure.
Next, try the Cam and Crank Position Sensors?
How many miles again? Check Timing Chain....for sure!
Now, if you can get your hands on a known working ECU, give it a shot.
You chould also do the "Learn Idle Air Volume" procedure.
Let me know if your interested. I can post a FTP link to download the enire Nissan Shop manual...FREE of charge, email me
info@ahsfl.net