I’m no great expert on brakes (can you tell?)
But - I can see the potential benefit of holes in the discs aiding cooling. Beyond that, and unless you’re into super-speeds and heavy, prolonged braking, I don’t see the benefit from grooved discs???
Put a bit of grease on the discs, that’ll stop it…
NO DON’T !!!
I’m with your ‘glazed disc’ explanation.
Don’t you have a couple of spares in your stash that you switch briefly, to rule in/out?
I think removal and cleaning of injectors would be a reasonable (and cost effective) stage one to try and address the problem, even if it requires buying a cheap sonic cleaner. If that didn’t work, I’d go to stage two and buy a known ‘good’ injector from someone (here) and replace each with it...
Ok chaps, update on @ChuggyFreelander ’s car…
Main issues for MOT are excessive smoking and handbrake. My advice was to sort the smoking first, if dealt with, then replace the rear brakes.
Seems to be an injector issue going on as the balancing range is between -5.4 through to 6.2, which seems...
@ChuggyFreelander
Off-topic, but as promised;
PB blaster is my first go-to for releasing rusty nuts and bolts. Soaking time is your friend here.
Owatrol Polytrol is brilliant for restoring your black trims on the car.
A lot of the 'go-to' stuff has been done by the OP already, including PCV and MAP, but we'll get some checks and read-outs and report findings.
The intake manifold and EGR has been cleaned also - @Arctic2 do you still have any cleaned + gutted EGR units available?
The injector balancing figures...