Re: XJ died, won't start
If the coil is cracked it needs to be replaced, even if it appears to operate normally it will allow moisture in which will affect it's output and reliability. I would venture a guess to say you may have an issue in the distributor. As the rust was building on that point it resists the flow of electricity which increases heat and starts to burn things from there down. If you had one wire that was bad it just means it is time to replace them all. The allowable amount of resistance in a spark wire is very very low. I would start with ignition coil and wires and see how it runs from there.
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We do not remember days, we remember moments.
Cesare Pavese