That'* a gap or bulb? I've never seen a bulb used to test spark. Not sure I have yet.

I can't tell anything from the picture. Looks like glare reflecting along most of it.

I guess, in a nutshell, you have seen this light up on something in an accurate and predictable manner such that we aren't being mislead by a faulty spark tester, right?

😉 whimpy lawnmowers.. no real spark. 😄😃

If only I could share an .mp4 video of it in action.. alas

Going to wind this thread up now.. after testing and replacing the Cam sensor and checking the ECU timing sequence at Start finally got spark back and it started.
Still has the RAP relay code for no valid reason though. That mystery remains.

Thanks for letting us know what fixed it!