cam101

Thanks for the great (and very accurate) advice, to conclude...

The garage sorted it in 2 hours, it was a blockage caused by the muffler on the exhaust shedding its lining (the hair). This led to a loss of compression and hence the inability to speed up!

(Hope that makes sense, it's kind of what the garage told me!)

They replaced the rear part of the exhaust, at a cost of just £42.

Thanks!