secondary injector module/ecu

[spork2367]

Originally Posted by GOLDCYLON

Folks I just want to say these are another Achilles heal for the early Z models as they are the components that allow the secondary's injectors etc to fire. Normally only available in a part out. In the later Z's this is done by the ECM.


GC

Continuation of the discussion from the for sale thread:

What does the secondary injector module actually do?

As determined by Marc's testing, all ECU's are interchangeable with the correct PROM. Which would lead me to believe that either the circuitry exists in both ECM's, or it's done entirely through the PROM.

One would think, that with the proper programming, a simple wiring change should be able to eliminate the secondary injector module from the car.

On another note, I have one of the DIYautotune megaquirt LT5 ECUs. When ordered, I had to specify 1990, or 1991+. They cited an internal wiring change between the two. Does anyone know if this is due to the secondary injector module? Why does the stock ECU handle both with a programming change, but the megasquirt requires internal differences to the circuitry?