Originally Posted by chaseincats
I'd suggest he check the plugs for the AFM and throttle position sensor for corrosion and break out the deox-it if there is.
EDIT (addition): I'm not sure if this is how it works, but what if he unplugged the throttle position sensor. That would isolate it as a test but I'm not sure if/how the car will run without it.
It would definitely be running off the AFM only until ecu kicks in full fuel.
1975 280Z F54/N47 MSA 6-1 Header 2.5 Exhaust