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Mueller
it looks like I possibly jumped the gun and blamed the sparkplug wires for my lack of juice to the plugs.....I tried two different coils, both oil-filled stock type units, when I triggered the coils manually and held the coil wire to ground, the spark produced was in my opinion very weak


I picked up a known good Bosch coil that i will test later on this evening (doing honeydo's right now or at least i am supposed to smile.gif )
brant
bump....

my car stranded me on the road yesterday, and although I haven't had time to diagnose it yet.... I'm suspecting the coil due to the fact that it was failing at high rpm.

so bump.. how do I check a coil

brant
lapuwali
Replace it with a new one.

Really, there's no reliable test. Some people say measure the resistance between the two side posts (should be very low, but not zero), and the side and center post (should be fairly high, but not too high), but that "test" has certainly failed for me before. Measuring inductance appears to be very difficult to do, or requires some special gizmo that's not seen much, and certainly costs a lot more than another coil.
brant
thank you sir...
I'm going to start a new thread so as not to totally hi-jack mike's...

b
KitCarlson
Mike,
A coil is not easy to test. On ohm meter will not show a single or a few shorted turns in the windings. Also shorts may only happen at elevated voltages.

You need a condenser in the circuit for proper spark, when testing manually.

Also "Danger", you can get shocked the primary voltage can go to 500V.
pbanders
Best test for a coil is to swap with a new unit. It's not such a bad idea to have a spare, anyway.

I've got an LCR meter so I can test a coil, IF, I know what the primary and secondary inductances are supposed to be. So, I still have to have a spare coil!
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