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240 How do I MANUALLY create a spark?

Set engine to tdc.
Loosen distributor bolt.
Turn ignition on.
Move distributor back and forth.
#1 plug will spark as you trigger the mag pickup.
I usually disconnect#1 wire and plug in a spare plug. Use a jumper wire to ground the plug body at the engine hoist bracket on the thermostat housing.
 
charge the coil, and suddenly remove power.

How?

Set engine to tdc.
Loosen distributor bolt.
Turn ignition on.
Move distributor back and forth.
#1 plug will spark as you trigger the mag pickup.
I usually disconnect#1 wire and plug in a spare plug. Use a jumper wire to ground the plug body at the engine hoist bracket on the thermostat housing.

Yes! Agree completely. I like CleanFlameTraps suggestion of passing feeler gauges thru the hall effect sensor. However, the goal is to do the least work and intrusion possible. Turning and engine to TDC and tweaking dists isn't ideal. I am looking for a clean and easy test.



multimeter set to ->]- and ground both poles to starter.

No. I guess I could also put a spare flywheel on a lathe and hold the RPM sensor above it!




No I am just an obstinate noob or a seasoned tbricker that refuses to advance my skills and tools. I just want to keep my head in the sand and fire parts at things.




I am thinking of ways to do it via the RPM sensor on LH2.4. I heard a soldering gun near the sensor will trigger it. No joke. Or what about jumper wires? Why can't I just tap the signal wire to ground and make a spark?
 
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I see you haven't bothered to read up on the old Kettering ignition since we last went through this.

Charge coil from 12V battery, discharge coil into ignition lead.

The ignition switch gates +12V onto the coil (sometimes through a ballast resistor that you can use as a current shunt to look at the charge profile of your coil if you are
sufficiently proficient with aforementioned 'scope), and the ignition computer pulls the -ve terminal on the coil to ground to charge it, and lets it float to let the coil discharge.

So on 2.4 or 2.2 (or 2.0, or the 240 reluctor, or the 140 points ignition.... get the picture?), you turn the ignition switch to the position you usually put it in to allow the car keep running after you've cranked it to start, and you short the -ve lead on the coil to the chassis somewhere.

I'm trying really hard not to be a condescending ****, but damn you make it difficult.
 
So you are saying Key on, jump the coil negative to ground quickly? Didn't work last time I tried.
 
So you are saying Key on, jump the coil negative to ground quickly? Didn't work last time I tried.

Yep. Check you have 12V on the coil. Actually you should have 12V on both sides of the coil on anything except a points ignition (depending on points position). The ignition computer should not start charging the coil until it detects the engine rotating (saves cooking the coil if you sit there with the ignition on) so the coil should have nothing pulling the -ve terminal down.

If you have some odd swine of an ignition system that does keep the coil cooking, just pull the -ve wire off first, then jump the terminal to ground. It is how the ignition computer makes fire, so it has to work (unless the coil is dead). If you want a good kick, keep your finger on the -ve terminal when you pull the jumper off. The level of profanity that results is a good metric of ignition system health.
 
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Car in question is a 1990 Volvo 240.

So I can leave my positive and negative wires hooked up, and simply tap the negative to ground with a jumper wire and get a spark? It didn't work.
 
Great failure and great success!

Grounding coil negative doesn't work. Tried it several times right now. Fail.

However, I had great success with jumping CKP sensor signal wire! It took the correct rhythm, but tapping a jumper to ground got the fuel pumps to go, IAC, to click and spark at my tester!
 
Well I couldn't get it to work. Probably over saturated the coil. I have tried it many times with no luck.

On a hall effect dist one could also tap the two hall effect signal wires together I believe and get spark. Easier than turning bolts and less intrusive=less chance of breaking something and disabling vehicle.
 
charge the coil, and suddenly remove power.


Ungrounding does work. Thats how points work.

I managed to get the coil to spark ONE time weakly today so far in my three times trying this. So far, all that happens is strong arcing from the jumper wires and that is it.

Have you guys actually done this test, or is it theory? I understand the theory of an ignition coil, but when trying to perform a test it doesn't work I tell ya!
 
I have poured thru dozens and dozens of articles and only one guy has claimed to test the coil by grounding the negative with a jumper. I can't even find that article anymore.

My argument is that you can't get the dwell correct just with slapping a wire to ground. I was using a spark tester again today and even closing the gap close to nothing made no change.

The purpose of trying to manually create spark is so I can create easy ignition system tests that tbrickers can do. So far, the best test I have created is jumping the signal wire from the crank sensor to ground. I can consistently get spark tapping it to ground with the correct rhythm. That lets the ignition module control dwell so that the coil actually sparks!
 
The power stage (ignition module) controls dwell on my 1990 240. I posed the question about hall effect distributor cars just to see what people would say about their own theoretical, and proven, test results. :wink
 
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