Re: VVC Running rich - Lambda?
I'm no expert but are there any holes in the exhaust system?
I was failing on emissions at my last MOT and it was only after hooking up the smoke machine to the exhaust we found a tiny pin prick hole in one of the welds on the manifold. It wasn't big at all but it was enough to throw the Lambda sensor reading out.
The smoke test revealed a couple of other leaks in the exhaust where the exhaust bracket is sandwiched between the pipes... not the best really, the garage was suggesting other ways to do it but I don't have time or energy to go mucking about with it!!