Right then, a brief update:

Fitted the new plugs and lambda sensor on Sunday afternoon.
Adjusted the CO pot and started her up. Seemed to start ok, (still takes longer than the old chip, for some unknown reason, maybe the babyboard I fitted?)

Took her for a long drive on Monday, my day off, and dropped in at SCC for a quick check.

Bunged the exhaust analyser up its bum, and the CO was at 0.5-6%

I was under the impression it needed to be at 0.9% (to be rich enough on boost, global modifier and all that) so I messed around with it but couldn’t richen it up without it switching to the conventional map (non closed loop).

As I didn’t wanna take up too much of pat and rob’s time, we got it running at about 1% CO but I think its too rich as it keeps swapping from closed loop to normal (I can tell this by the voltage output from the lambda).

Upon chatting with Stu after I had got home it seems perfectly fine to have it running at 0.5% CO and 0.9% is the maximum value. So all the fiddling was unnecessary, just my luck!

So I am planning on going back to SCC at the weekend and getting it running.

Then put a full tank of juice in it, and seeing what the mpg does now