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240 How do I MANUALLY create a spark?

Ok. fine. yeah I know some amplifiers do, some dont. Doesnt really matter in this thread.

So can somebody show me a video of them making a spark just tapping the negative to ground?
 
I guess similar things are available in the USA, but here in the UK I have a gizmo that will create a low current signal pulse and trigger modules, and it also will receive pulses from hall effect, optical and magnetic sensors and flash an LED if it "sees" anything. Wouldn't be without it, I think it's discontinued now, but I have seen similar things advertised. Checks for ABS wheel speed sensor signals, too, a great tool I use every week for something or other.

EDIT, no, I think it's still available see ignition tester lower down this page, but I do not see it in the price lists. Roger Bywaters designed the electronics for the Jaguar V12, but don't hold that against him ;) :

http://www.jagweb.com/aj6eng/misc_bits.php
 
Lord_Athlon said:
If you want to know how to force an ecu to trigger a spark event, build a timer circuit and move on.
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No. I have already stated the purpose of this thread is to create easy test methods that the average tbricker can easily reproduce.

My conclusion is that if I wanted to test for spark, best method without cranking the engine, or if ignition is dead and crank sensor is suspect, I am gonna use my jumper wire to ground out the crank sensor signal method. That is all the flywheel really does. Just sends the signal back and forth to ground. In essence.

Those that have told me simply to ground the coil negative I am saying that they are wrong until they show me otherwise.

I got an AC voltage measurement at the coil negative that increases Voltage and frequency with RPMS. But what does it mean?
 
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Like the injectors in most EFI systems, the coil has a permanent ignition switched 12V + feed and the ecu controls a semiconductor device, probably a FET, that grounds / un-grounds the coil negative each time a spark event needs to occur. How long the grounding / un-grounding occurs is called the dwell time and probably varies under ECU control. By supplying the coil with 12V + to the positive terminal, and rapidly manually grounding and un-grounding the negative terminal with a bit of wire you can A: get it to produce high tension, and B: maybe give yourself a bit of a belt as the magnetic field subsides and it also induces a highish voltage pulse in the primary winding, so take a bit of care ;) Use a scope with caution, it won't like a few tens of kV on its input.... A scope can only read and show pulses, it can't trigger an event, so is inappropriate for what you want to do.
 
So can I just slap the coil negative to ground like people here are suggesting to create sparks and flames?
 
cwdodson88 said:
He's wanting a way to test for a bad coil vs a bad cps, I think...
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Basically. Yes. I want to create low tech tests that an average college student tbricker can easily recreate without the need for high end tools such as a scope.

I have yet to try waving a soldering iron near the crank sensor to create a spark. That one should be fun.
 
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Zach, you are currently on some sort of high horse with your attempt at advanced diag techniques, and you have nothing to back it up really.

You also just said 9v batteries are AC.
 
If you found an old points type scrap distributor and drove its spindle with a battery electric drill you could use the points and condenser (capacitor as it's now called) to pulse the coil negative to ground and get a series of fairly fast sparks from the coil king lead. A modern EFI system just uses a semiconductor turned on and off under ECU control to ground the coil instead of points, and a "map" to change the timing of these events instead of centrifugal weights turning the points operating cam relative to its drive gear, thus advancing the ignition from its static setting. A basic radio ham or EE student could cheaply build a semiconductor circuit with varying pulse width and speed to do this for a few quid (dollars).
 
ZVOLV said:
I am gonna use my jumper wire to ground out the crank sensor signal method. That is all the flywheel really does. Just sends the signal back and forth to ground. In essence.
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This is not how a Variable Reluctance sensor works.
 
I feel like this shouldn't be terribly complicated. I'm a MechE, though, so no electrical vocab here :lol:

1. Unplug ignition coil low voltage ground.
2. Unplug ignition coil wire to distributor cap (high voltage ground).
3. Connect spark plug wire to high voltage ground on ignition coil.
4. Connect spark plug to that wire.
5. Ground the spark plug [thread] on the chassis, or somewhere (use a wire, don't want to hold it while you're doing this).
6. Connect one end of another wire (not being used elsewhere) to the ignition coil low voltage ground.
7. Turn on ignition.
8. Take other end of wire from step #6 and tap it against a good ground. Spark plug should spark at each release.

Step 7 could be replaced by "Connect 12V battery positive to positive ignition coil terminal", then make sure all grounding is done on the negative battery post.

I've never independently tested a coil, but I suspect that is how I would do it. Would I die?

30wmemd.jpg
 
mtd240 said:
I feel like this shouldn't be terribly complicated. I'm a MechE, though, so no electrical vocab here :lol:

1. Unplug ignition coil low voltage ground.
2. Unplug ignition coil wire to distributor cap (high voltage ground).
3. Connect spark plug wire to high voltage ground on ignition coil.
4. Connect spark plug to that wire.
5. Ground the spark plug on the chassis, or somewhere (use a wire, don't want to hold it while you're doing this).
6. Connect one end of another wire (not being used elsewhere) to the ignition coil low voltage ground.
7. Turn on ignition.
8. Take other end of wire from step #6 and tap it against a good ground. Spark plug should spark at each release.

Step 7 could be replaced by "Connect 12V battery positive to positive ignition coil terminal", then make sure all grounding is done on the negative battery post.

I've never independently tested a coil, but I suspect that is how I would do it. Would I die?
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That sounds like how I've done it... I usually just skip to step 7b though since most any electronic ignition (i.e anything but points) will either shut off power to the coil or not charge the coil without seeing a significant RPM signal through the ignition computer.
 
ZVOLV said:
That little part was actually a bad joke. People around here like to flame me for suggesting using advanced tools and techniques and interpret it as arrogance. I am learning advanced diag techniques and trying to share them with the community. I expect the blowback from certain members.
You might think you are joking, but you haven't lived till you go to check spark and have a CCV fume explosion.




Basically. Yes. I want to create low tech tests that an average college student tbricker can easily recreate without the need for high end tools such as a scope.
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You can get an ohm meter that will do the job for less than $4:e-shrug:

If you are having trouble getting a spark, look again at the breaker point system.

Also don't put 12V to small engine mag ignition coils, most of them blow up if you do.
 
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