Injector plus other issues

[Greenoaks]

Hi - 

We bought our son a 2010 1.6 HDI XTR Multispace last year. Its got 100k miles and reasonable service history. After a few months, he's had juddering which turned out to be a bad injector. The garage has sorted this but says there is an underlying electrical issue, which might explain the slight white smoke, dipped headlight bulb  not working and fast flashing indicator issues. The garage say they are not 'auto-sparkles' so say they can help no further. Can anyone recommend a decent garage with Berlingo experience near Bangor, N Wales, who might have a decent stab at it please?

Thanks

Daryl