This is directly from a 1994 Nissan Sentra FSM(Factory Service Manual) - GA engine section
MASS AIR FLOW SENSOR MALFUNCTION
If the mass air flow sensor output voltage is above or below the specified value, the ECM senses a mass air flow sensor malfunction. In case of a malfunction, the throttle position sensor substitutes for the mass air flow sensor.
Though mass air flow sensor is malfunctioning, it is possible to drive the vehicle and start the engine. But engine speed will not rise more than 2,400 rpm in order to inform the driver of a fail-safe system operation while driving.
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THROTTLE POSITION SENSOR MALFUNCTION
When the output signal of throttle position sensor is abnormal the ECM judges it as a malfunctioning of throttle position sensor.
The ECM does not use the throttle position sensor signal, but judges the idle position by the amount of fuel injected and the engine speed.
Operation of Malfunctioning Throttle Position Sensor:
When engine is idling - Normal
When accelerating - Poor acceleration
I never said it was well worded
but either of these could be a potential problem.