I've also started on the mechanical side of things with a compression test. The results were ok on all cylinders apart from 1 and 4 which was down on compression around 15psi below the other. I'm thinking it's been sat for so long and not had a good run in over 4 years hence my plan is to give it a full mechanical service including new ignition components, EV6 injectors, shims, TB sync and some other works part of normally servicing. I'm hoping this combined with a good blast on the road will help remove some of the carbon deposits and hopefully restore compression back within tolerance.
The usual mayo signs haven't appeared in other parts of the engine so again my theory is that due to sitting for so long condensation has led to this build up. So I'm going to clean it up and after the service see if I get any further build up.
With M cars the M stands for Money so as a last resort I will pull the motor and do a full rebuild. Until then I'm being optimistic and hoping for the best.
If you like what you've read I'll keep on updating this thread with my progress.
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