My v6 top end rebuild is now complete
Just the hurdle of getting an MOT.
I replaced both head gaskets (ful gasket kit so manifold etc gaskets also), valve stem oil seals and both the '1st stage' lambda sensors , front and rear (bosch, exactly as original).
MOT test today, passed on all counts except for emissions as per below:
CO max 0.3 actual 1.28 FAIL
HC max 200 actual 74 PASS
Lambda 0.97-1.03 actual 0.990 PASS
2nd Fast Idle
CO max 0.3 actual 1.593 FAIL
HC max 200 actual 42 PASS
Lambda 0.97-1.03 actual 0.964 FAIL
CO max 0.5 actual 2.461 FAIL
So any advice on where to look next gratefully received. Being a CF3 model there are 4 lambdas and 4 cats...
My instinct is an air leak between the first and 2nd stage cats (those flexy pipes??) Any past experiences (and numbers) would be a great help.
This rebuild has been long and challenging...I'm not sure I'll do it in a hurry again. But the 10 mile drive to the MOT station was sheer pleasure. The beast has never gone so well in its life, so at the moment this MOT hiccup is only feeling like a minor hurdle...
Thanks as always for any help,