TBI Injector polarity

[PlayingWithTBI]

Hi

regarding that they fire synchronously, how does the ECM know which bank is firing as the tbi lacks crankshaft position sensor?

BR
/Alex :)

Probably doesn't since it's a wet manifold system. I guess it's just a balancing act between injectors. I just find it interesting that timing would coincide between manifold design and injectors firing.

Does your engine actually have both red wires or, is it a misprint? Not that it matters - just curiosity.

[AlexanderHL]

Probably doesn't since it's a wet manifold system. I guess it's just a balancing act between injectors. I just find it interesting that timing would coincide between manifold design and injectors firing.

Does your engine actually have both red wires or, is it a misprint? Not that it matters - just curiosity.

:)
Couldnt find photo, but yes red/blue and red/green wire on car also :)

[steveo]

many gm dual injector tbi systems have two modes, one where both injectors fire in a pattern left and right, and one where both fire together. there is usually an rpm threshold for this so at higher rpm they fire at the same time.