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Injector dead time

As Kenny already pointed out, the spike you see there is because the collapsing magnetic field in the coil inside the injector is inducing a current. That would happen even if the injector would be mechanically stuck shut. The opening and closing delays are more of a mechanical phenomena.

Not exactly, but close enough for practical purposes. When the field collapeses in some instances, where the pintle is stuck, the view on the scope will be slightly different. Very similar to this, but when you scope other injectors on the same vehicle you will see the difference.

and shop n00dz if I can get any of these contractors to call me back :sigh:

If that's the case I'm going to have to ignore you too Kenny.
 
Not exactly, but close enough for practical purposes. When the field collapeses in some instances, where the pintle is stuck, the view on the scope will be slightly different. Very similar to this, but when you scope other injectors on the same vehicle you will see the difference.

if the pintle is stuck, sure. The other thing to consider is the stability of fuel flow through the injector (which is non linear below a certain point on most if not all injectors), which may not coincide with the stabilization of the mag field for a number of reasons.. most of which at a glance appear immaterial, however when we're talking about a value generally around to below a millisecond (and increments of tenths and hundredths of a millisecond) immaterial things matter, and busting out the scope will get you pretty much in the same ballpark as a guess, and you'd probably end up closer to the real value if you used an educated guess based on other injectors from the same age and family. and again, we'd be splitting hairs over tenths of a millisecond.

Far more important really, is the dead time delta vs voltage-especially on injectors that will be far beyond the opening time at idle on any kind of engine common to this forum.

When opening time becomes really critical is when you have, say, 2200cc injectors and you're trying to get a small engine to idle, and your idle pw's will be down around the opening time. too low and you may incorrectly get into the unstable portion of the injector's capability, too high and you may not be able to dial them back.


If that's the case I'm going to have to ignore you too Kenny.

well, you gotta do what you gotta do.
 
You can see the small inductive spike from the pintle moving on the downward slope of the spike. That little hump is the pintle moving. A stuck injector won't have that.
 
I'm running my own race. Take it or leave it dude.

I am aware of my own egocentric dialogue, but the point of this forum is to share information. Don't like it, put me on ignore list too.
 
Zach...seriously...check out ATG to get some skills and really put that drive into what you do daily. Their classes really get into it and can really help you pick up the skills to really make some cash on the diagnostic side of things. They show you the quick and dirty ways to check stuff out without removing parts, actually diagnosing stuff rather than parts cannon'ing it.
 
/begin ralph "when I grow up I want to be an ase master tech or a caterpillar."

End ralph/
 
For ****'s sake. Oodles of hate circle jerking and no word on a good spec for this goddamn injector at 13.2V using a Megasquirt v3 board.

You need to go get laid. All of you.
 
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