So the way I was able to do the crank bolt was with an air gun. I asked my mechanic about how to stop the engine from turning when doing it the way you are, and he said to access the flywheel and use something to jam that to stop it from turning.
You may not have to do all this, I managed to...
I’m also now following this thread with the same issue apart from having zero issues with idling. I don’t get any drop in revs etc. As soon as I apply throttle it starts carrying on and even backfiring.
I’m lucky enough to be good mates with my mechanic, so we completed a bunch of work on it at...