js550 no spark?

[Matthew N-J]

Hi,

No spark on my 92 550sx was running ok then nothing, i checked the ignition coils under the flywheel and one of them (cant remeber now which one) was broken (open circuit) so i replaced it. still no joy, is the coil likely to have been damaged as a result? can i test it?
how do the two coils (under the flywheel) work with the coil and overview would be handy to try and work out what is going on.

Thanks

[Joe St. Louis]

When checking for spark I always like to go backwards. That means I start at the spark plugs and work my way back, making sure that the component I'm checking is perfect before I move on to the next one. Replace the plugs. Test the spark plug caps for resistance. Then the Spark Plug Wires. Then Stop button. Then Ignition Coil. Then CDI and lastly the stator coils. :D [img]/graemlins/winkanim.gif[/img] [img]graemlins/cwm3.gif[/img]

[arch701]

Hi

One of the coils is the stator which provides constant power to the CDI unit and the other is the exiter (trigger) which causes the capacitor in the CDI to discharge through the coil.
(The third BIG coil is for charging the battery and not relevant at all with engine running)

If both coils read resistance within spec, then test the ignition coil (both primary and secondary) However, you may have an intergrated CDI/ Ignition coil unit, which makes it more difficult.

Now you have to start replacing items. I have a brand new unused intergrated CDI/ coil if you need it.

Happy hunting.