Bad Pickup Coil?

[austex]

Hey guys, I have an early '74 260Z with the stock transistor ignition system (except for MSD Blaster 2 coil) and original distributor.

Today it would crank strong but not start, and I found later that there was no spark. The resistances on the coil were out of spec, so I went ahead and picked up another one. Still didn't start.

So I checked the pickup coil the way I was always taught to: connect an ohmmeter to the connector, then tap the coil lightly and see if the reading changes. And it did: with an initial reading of 727 ohms, it changed about +/- 300 ohms with each tap.

Is that the problem, then? I ask because I've never run into a bad pickup coil before. Are there other tests to run to determine if it's bad?

[alhbln]

Hey guys, I have an early '74 260Z with the stock transistor ignition system (except for MSD Blaster 2 coil) and original distributor.

Today it would crank strong but not start, and I found later that there was no spark. The resistances on the coil were out of spec, so I went ahead and picked up another one. Still didn't start.

So I checked the pickup coil the way I was always taught to: connect an ohmmeter to the connector, then tap the coil lightly and see if the reading changes. And it did: with an initial reading of 727 ohms, it changed about +/- 300 ohms with each tap.

Is that the problem, then? I ask because I've never run into a bad pickup coil before. Are there other tests to run to determine if it's bad?

It is quite rare that the coil in a magnetic pickup breaks, but it has happened. A fluctuation of 300 ohms might rather point to a broken cable, have you checked this by moving/tapping on the cable itself? I just had this issue on a Lucas distributor, where the engine would stop for no apparent reasing while driving, we discovered then that the pickup cable leading to the amplifier was broken.