I am building an RX4,


build thread here:

https://www.rx7club.com/old-school-o...oject-1094233/



I am putting an FD engine in it.

Will the Stock ecu work if it is not receiving inputs from all the normally present FD sensors?

 

You will probably end up with codes if sensors and output solenoids (such as twin turbo control or emissions controls) are disconnected. Some failures can result in limp mode, or a low rev limiter. Which things were you planning to leave disconnected?