Hi Peter – I don’t think there is a repair house in the UK – this company is in Germany – not that far – http://www.123ignition.de/repair/123ignition-repair.aspx
I’m sure you’ve checked it’s wired the right way round and that it’s got a decent earth but I’m not sure what happens if the coil goes bad in some way or other.
It would be good to know how this develops as I think quite a few of us run 123 distributors. I have them on 2 cars without problem – so far!
Chris