Thank you for your responses TVPierce and Johnatahn1.

There does appear to be a cat but certainly no position to fix a lambda sensor in. I have checked under the carpet and found wiring for one, attached to one side in a special holder.

I can only guess that the fuel injection on this car is no more sophisticated then the SU carb on my old Rover Metro!

As for the vacuum gauge it shows roughly 1/5th to 1/4 from the left when started from cold ('choke' on) and near-fully to the left once warm running idle.

Just to reiterate the fuel consumption remains around 20-21, consistent with urban traveling and the engine has none of the signs of hesitation or rough idling. It's just the get-up-and-go-go-go! There are kids around here with Nova's and Clio's that need knocking down a peg or two! (because I'm fed up of them being able to overtake me )

Thanks once again,

Glyn B.