If the coil is designed or 'tuned' to be in-spec and also how it is tuned with the detector, or the GB setting. I've done that in the past when I have had several 'turn-on-and-go' Tesoro's (preset G

and I'd check them by swapping the coils around and find the best match-up before I sold them.
Just take care of those coils and that specific Golden µMAX , especially since you have one that works as intended.
Monte
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