Nissan Repair: 86 nissan z24 miss, nissan z24, mass airflow sensor

Question
86 720 z24 has high rpm miss/vibration. fresh tune(plugs &wires,rotor&cap),replaced both coils,firing order correct. low rpms smooth.sluggish start,timing is set,sometimes rough idle.eccu has not been read as have to pull seat to switch it

Answer
Leo,

It is probably the mass airflow sensor but read the codes to be sure and if none are present get a Haynes Manual and backprobe the connector and validate the readings are good per the book.  But, for me it is the mass airflow sensor.  The rough idle is a give away as is the high rpm miss.