classic fault code 23
 

Hi I have a my00 turbo and ive got fault code 23 coming up. The car coughs and splutters once you get to around 4000rpm and using alot of fue obviously as the ratio is being calculated wrong, so far I have trie:

Changing the maf for a new one.
Tested for resistance at the connection and there is.
changed plugs.
leads.
closing the gap on the connectors
really dont know what else to try, for the last month the car would miss fire at high revs underload but no light so assumed it was plugs or leads so these were changed. The other thing is that the light will some times go out and come back on a few minutes later or even flicker for a few seconds.
Any further advice or ideas would be appreciated.
Thanks

Lambda sensor possibly, whats it like from cold start?

Its fine from cold, but once warms up revs hunt and occasionally cuts out, I thought lamba sensor had its own code?

Btt really need to get this sorted