how do i reprogram my ecu 90 maxmia automic

 

don't try reprograming anything until you've reprogramed your fingers to type properly

Seriously, do a search on google - you'll probably find it much easier to add a chip or piggy-back ecu rather than reprogram the ecu.
The Nissan fuel injection system (ECCS) is based on the Bosch Motronic system. There are software / hardware systems that can look at & decipher the ecu, but I don't think the memory chips are writable e-proms - at least not without specialist equipment.

 

nice, I learn something new every time I look around, haha

 

jwt does nissan ecu reprogramming but for a hefty cost. something like 550-600 dollars.

 

That is easy, plug it into a computer and type in C:/Format that will format the ecu so you can input a new DOS code into it