Optional update for Emissions?
I've got my 17 reg GLA220 4 matic in to investigate why the Start/Stop never works and the lady told me there was an 'Optional' update available for 'Emissions'
She was a bit vague but stressed it was entirely up to me whether I had it or not.
Wondering if this is a VW style update which will screw (or correct) my mpg or performance
Has anybody had any experience of it yet?