Newbie owner - firing on 1 cylinder only

[SunnyBus]

Update...so, in summary, never going back to garage who totally were rubbish..she needs a new alternator..and now probably a whole new engine as on the way to different garage the slight (not even dripping on the drive) oil leak became catastrophic and had total loss of power on the M4...2 children with me, really scary, rude horrible break down man. But...at least now she will get full attention from experts at voodoo.

[Ralf85]

Oil leak from where? I had a massive sudden oil leak some years ago. The oil warning light came on so I stopped the engine. That turned out to simply be an oil gasket failure around the rocker box cover. I always carry spares. So a new 75p gasket fitted, a top up with oil and bingo we were running again. Good luck with yours.