Injector Cycling

[Frederic Breitwieser]

>Yup, understood. I was just saying that you don't really need to fire
>the actual injectors, to figure out to a pretty close approx. the fuel
>delivery, but rather look at the scope & measure the pulses. Actually,
>Bruce said he has a frequency counter, so he can use THAT to measure the

Got my 100Mhz scope today from Steve (Thanks Big Guy!) and hooked it up for
a test, works great.  Now to have it calibrated, then off to the ECM.  By
then my workbench should be reorganized in such a way that I can actually
see it, and have a place to work.  Going to be working on the '148 ECM from
86 FWD cars and 87 GN's.  have it and the entire wiring harness (also the
engine, digital dash, and all the dopey toys that go with it).  Big, big
harness.  Though I probably could skip the body harness, and just keep the
digital dash and the sensor portion of it.

>instead of running with all this "apparatus" of battery and liquids
>squirting every which way, all the time.

True.  I like making things complicated, its my nature unfortunately.

>a PC power supply was made, except that with 8 injectors and an 8-cyl
>IGN going, it might not have enough current. (Actually, you wouldn't
>need to run the IGN coil, either, which would save even MORE current,

The best bet is to comb flea markets that have vendors of electronic crap.
I bought a 12V 50A (continuous, 70A peak) power supply for very little
money.  This is what I test most of my car stuff on.  In fact, in the last
few car-rewires (older vehicles being restored) I tested the harness end to
end on the garage floor.  Just didn't turn on all the lights at the same
time :)

>MODULE, not the coil; it (the coil) doesn't actually have to be there
>for the IGN module to completely function 100% normally.

That's good information :)

>P.S. I've run a setup like you describe to measure injector flow; man
>what a mess! And try and find a solvent that's REALLY non-combustible,
>nor gives off fumes. Especially for Bruce with his lungs on perpetual
>overtime, I wouldn't wanna have to do THAT everytime I wanted to run my
>"simulator". I'm not real sure, but I'd guess using water would be
>asking for trouble.

Yes, the injectors would clog.  I tested the injectors I pulled from the
yard to get a matching set of six by using gasoline.  Not the brightest of
moves, but I didn't smoke near it, that's for sure.

>ECU, unless you were checking for noise immunity. B)

Its a GM ECM, of course it has noise <smile>

Thanks for the info !


Frederic Breitwieser
Bridgeport, CT 06606

Homebrew Automotive Website:
http://www.xephic.dynip.com/

:When in doubt, by two."
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