Well I'll let the vets answer this but after having success today I'll give it a shot. I think the top coil is due to it being loose considering it's not a full wrap. It could also be the other
coils close to it are not spaced evenly. It could also be the distace between the top coil and positive post, try to get as close as possible without touching and without strangling the wick. Believe me it's a pita and constantly giving me probs. But today I've made 2 working
coils in a row at 2.2 ohms! It's worth the aggravation.
A short is actual short in the coil where it stops firing, your device would throw an error code and you may see the coil pop like spark in a certain area. It is usually just due to oxidation issues in the wick