Injector supply voltage & positioning.

[Jonathan R. Lusky]

Bohdan L Bodnar writes:
> 
> Peak-and-hold injectors typically are driven at full supply voltage (less
> voltage drop across driving transistor) for a short time (e.g., in GM's
> throttle body systems, this time is 1.5 ms) and then power is drastically cut.
> The idea behind peak-and-hold injectors is the same as in pull-in and hold-in
> windings on starter solenoids:  it takes more power to overcome static
> friction than to overcome dynamic friction.  If one 'scopes a peak-and-hold
> injector, one will see two distinct back-emf "kicks" across the injector.
> I've never seen peak-and-hold injectors used for anything other than TBI
> systems.

I don't know what else uses them, but I know the Buick GN and the
Flex-fuel Chevy Corsicas use peak-and-hold injectors.  Most racing
applications use peak-and-hold too.

-- 
Jonathan R. Lusky                        lusky at knuth.mtsu.edu
http://frank.mtsu.edu/~lusky/               (615) 726-8700
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68 Camaro Convertible - 350 / TH350  \_/ 80 Toyota Celica - 20R / 5spd