Here is a post from my thread about how to test a coil.
Well guys I diagnosed the fault and fixed it!
It was the coil, I managed to get one through work.
I tested the new coil compared to the old and the old coil had lost half its resistance! Hence no spark.
To Test...
If you use a multimeter and set it to ohms, put one lead on to the positive or negative terminal and the other onto the output of the coil.
If your coil is good you should get a resistance of around 15.75kilo ohms so that's 15750 ohms.
My knackered coil was 8000 ohms.
I did other tests before this that lead me to test the coil which are as follows.
Remove dizzy cap, rotor arm and plastic housing to expose the coil and hall sensor etc.
First test if you have 12v at the coil, so turn the ignition on. Then use a multimeter set to Volts DC, put the red lead into the positive side of the coil and the black to any chassis earth.
You should get a battery voltage reading.
Second test is to check the negative side of the coil is getting a pulse from the hall sensor.
For this I used an ossiliscope, but you could possibly use a test light with an earth function.
For this test you need to set the ossiliscope to a scale where you can see the waveform clearly, I used a 2-5 second delay on a 20v scale.
Place the black lead to chassis earth and the red lead to the negative side of the coil, then crank the engine.
You should see a waveform consistent peak and trough squarish waveform.
If you need to I can provide pictures of needed.
In my case I had battery voltage at the positive, so I knew there were no fuses gone etc.
And I have a good waveform / hall sensor.
So was all pointing towards testing the coil.
Also in the original post with the multimeter reading of 0.74 ohms is just a continuity check across the contacts.
Sorry for the boring lingo but you never know it might help someone else one day.
Last edited: Jan 25, 2016