Hi all:
Borrowed a buddies MFJ-986 and played around a little on 75m last night running 500w and there was no spike.
My own tuner was broken down and before it was, it arced and popped on my buddies antenna and he discovered that my roller inductor was burned in a couple of spots and there's damage to the capacitor.
So I wasn't mistaken after all. So will order those parts, have my tuner fixed and hopefully will get a few years out of it.
73:
Mike VO1AX