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17

I'm sorry if this ends up being a lengthy answer. The answer to this question is more historical than anything else but first a little background. In a waste spark system an ignition coil has two spark plug outputs unlike every other system only having one. Each ignition coil is hooked up to two spark plugs. These spark plugs reside in two opposing ...


11

Unfortunately no. This is because the primary and secondary windings don't use the same wire. The primary uses a few turns of a thick wire. While the secondary uses many turns of a thinner wire. The reason for the thinner wire is that when the voltage is stepped up and current is stepped down and a thinner wire can carry the necessary current.


9

IMHO the only reliable way of telling the winding relation would be to feed an low voltage alternating current with known amplitude into the primary winding and measure the amplitude of the secondary. Attention: You could easily generate a potentially fatal tension, please do this only if you are experienced with high tension and can apply the necessary ...


8

Voltage drop problems are very common in multi component, multi interface systems. For instance the starter motor has a cable that runs from the battery to the starter. The cable has ring terminals on the ends and those terminals are bolted to the appropriate component. High resistance at any of the aforementioned connection points is a recipe for voltage ...


8

Since you said it has Ford on the case, this would most likely be a coil for a Model T. I don't exactly know how you'd test it, but I found this document from a Model T Ford website. I think it would be very hard to try and test, as there are adjustments of what I'm calling the top (to the left in your picture). There are adjustments needed for the vibrator ...


7

Yes you should ground the spark plug. In your case the spark plug was close enough to the block to still jump the gap. If the plug was far enough away from metal nothing would have happened. On a separate note. When testing for spark it is recommended to use a spark tester. Using a spark plug is a poor test of the ignition system. In free air the spark ...


6

Be it known that I, Joseph A. Williams, a citizen of the United States, residing in Cleveland, in the county of Cuyahoga and State of Ohio, have invented a certain new and useful Improvement in Ignition Apparaatus…. (U.S. Patent #1,092,417) That coil was used on model T Fords here are a little bits of info you might like complete with a link for you to ...


6

Some four-stroke engines did have wasted spark ignition. The basic advantage was not needing a distributor, which was one of the less reliable parts of the ignition system. Wasted spark systems were used long before plug-top coil packs came into common use. The reliability issues are not so important with modern ignition components. Wasted spark ignition ...


6

There are three tests that can be preformed using a multi meter. A DIS type coil that services two cylinders works like a transformer. The primary windings are controller by the ECU. The secondary windings are the output to the two cylinders. The primary and secondary windings should never touch. Using the ohm function check the primary and secondary ...


6

More than likely, you have an air leak If you haven't cleaned out and rebuilt a bunch of 4 carburetor banks in your life there is a good chance you have accidentally created an air leak in the system. Unmetered air will create the symptoms you describe. The giveaway on most lean conditions is the falling idle. It idles high and is getting enough fuel but ...


6

You could avoid the shock risk mentioned by @Myself, perhaps at the loss of some precision in the measurement, by applying the known source to the secondary winding. That way you're using the coil as a step-down transformer, instead of a step-up transformer.


5

Go with the standard replacement (the warranty choice is left up to you). High output coils are used in modified engines that have higher combustion chamber pressures from either higher compression, boost, or a combination of both. Save your money, unless you plan to turbocharge the 626...


5

AKA Trembler Coil The trembler coil was a device called a Ruhmkorff or induction coil, widely used in the 19th century.[3] It combines two magnetic devices on the same iron-cored solenoid. The first is a transformer, used to transform low voltage electricity to a high voltage, suitable for an engine's spark plug. Two coils of wire are wound around an iron ...


5

Background You have two coils on that motorcycle. One coil is for cylinder 2 and 3 the other is for cylinder 1 and 4. It utilizes what is known as a wasted spark system, the spark is fired off on TDC compression and TDC exhaust strokes. You apparently have an issue with one of your two systems. Each system, as you probably know, is comprised of two ...


5

Pᴀᴜʟsᴛᴇʀ2's answer is pretty much correct, at least for Toyotas (the linked post in the OP was for a Lexus aka Toyota). Here is some extra detail. Also "feedback" is used for different things in different ignition systems. Toyota/Lexus (Catalytic Converter Overheat Protection): This is from the official coursebook for Toyota's EFI/TCCS training course #850:...


5

There are a number of ways to go solid-state ignition and there are a few open source projects that allow you to build your own ECU and loom and utilize an ignition system from something else. One system that instantly springs to mind is MegaSquirt which is a programmable ECU project that uses Ford EDIS parts. Depending on the engine configuration you have ...


5

This issue is, you have serious cylinder pressure (or should I say, non-pressure) issues. The pressure test results you give (as long as the test was done correctly), shows a massive drop in cylinder pressure from where they should be. I'm not entirely sure where the Honda engine should be, but I'd bet it should be somewhere in the 150-180psi arena and ...


5

The usual idea is that with 2 wires; one is ignition controlled 12v and goes to the resistor (block on the side with two terminals) so that the coil receives about 9v during normal running. The other wire is 12v when the starter is operated and is used to feed the coil with 12v so it gets a higher supply voltage during starting - to offset the voltage drop ...


4

To be honest you won't get far with a DVOM. While vini_i's answer is correct you can't do this while the car is running. You should be looking into buying a digital storage oscilloscope if you want to test primary and secondary ignition. The uScope is a good beginners scope: Along with a low amp probe for testing the primary ignition coil: And a ...


4

Like @ Paulster2 I have never heard of this. I suppose it is possible if you had a coil on the edge of failure that it might fail while overheated. Resistance is a function of temperature. The more heat the more resistance, more resistance generates more heat and so on. It just seems odd that he knew to bring the ice. Maybe he was also being prepared for a ...


4

It's me, your future self. So it turns out that you're an idiot and all you had to do was fiddle with the choke. That little lever on the carb? That's the choke. I forget which way is open and which way is closed, but if you do the following: Push the ignition switch. If it doesn't start, move the choke lever to the other (closed) position. Push the ...


4

Check out the General Technologies TA500. This tool is quite inexpensive (for its incredible capabilities) and very flexible. Perhaps not for the DIY set, but there's no probing involved and it allows you to do coil-to-coil comparisons in seconds. TA500


4

The ignition confirmation signal is a comeback signal to the ECM. This tells the computer a successful spark has occurred: the coil has launched it's goods. When the signal fails, the computer knows there's an issue with the coil or the ignition circuit and will send a fault code, then notify the driver with the glorious check engine light.


4

There were already good answers, I'd like to add some points and also write something about the inductance. Here is a sketch of a typical coil: (Source) Resistance There are in principle two reasons why there is no correlation between resistances and windings. Therefore, keep in mind that resistance depends on length and diameter (gauge) of a wire. ...


4

Coil on plug has several advantages over conventional distributor type systems: 1) Less voltage loss from the coil to the plug. With fewer connections and the elimination of the distributor rotor to cap air gap. 2) Can be used in conjunction with injector control to have the ECM perform misfire diagnosis. 3) The ability to control spark timing to ...


3

Most electronic ignition systems are INDUCTIVE on cars modern vehicles. The energy available for the spark is stored in the magnetic field of the coil. This energy is released when the coil current is broken. The old mechanical breaker points have been replaced with a solid state switch. The energy is proportional to current squared before saturation. So ...


3

To test the coil, as you said there's only one cylinder that isn't working, just switch the coils of two cylinders. For the spark plugs, again you'll just switch two if you want to test one against the other, however unless the spark plugs just got replaced, I would generally replace them anyways, as it's so infrequent that you get in there.


3

Your spark plug was loose If the spark plug was loose and gone, based upon your comments, the coil did not pop out of your head, the sparkplug popped out of your head. The last change of the sparkplugs may have been the cause where this particular plug was not properly torqued down in your head. If your threads are stripped in the head, which I doubt, ...


3

You should be able to do this with a basic set of hand tools (ratchet/socket set). I don't know what it involves to get any covers off (may require some torx sockets or drivers to remove, though is probably only connected by some 10mm bolts or fasteners). The coil itself is a "coil-on" configuration which, in and of itself, does not require any tools to ...


3

In my experience, you are not describing a misfire. A misfire is a lost power cycle. It would typically be evident during steady engine speeds, or especially noticeable under the load of acceleration, which is not what you described. What you are describing is "Decel Pop". This occurs when the engine returns quickly to idle from high revs. It can be heard ...


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