I built a few racing motorbikes many years ago and used to buy my titanium fasteners from the states - much better prices than here.
I even had a few large fasteners made up for suspension components and they still seemed to be working out cheaper than that set of head studs .....
I don't have much to offer here I'm afraid - but the first thing everyone always seems to say is check the loom ?
When oil reached my ECU is did odd things like that - and they seemed to increase in frequency the more oil there was.
You can rule out the MAF by just disconnecting it - so it falls back to the ECU default setting.
My error - I thought it was just about normal ratchets.
I looked on my phone and on that the picture looked to be a normal open end and a ratchet - not an open end ratchet ...
Sorry !!
I have a set and use them a lot - I got the halfords professional ones on one of their deals.
You're right in that they aren't the tool for brute force to crack a nut - but they definitely aren't a gimmick for me.
For the engineering though that represents very good value.
But I'm perhaps in the same boat in that I could afford one - but couldn't afford to pay someone to fit it.