Need more information to give an answer, Including the year, type ie Vectra B, Ecotech, Petrol Diesel?
1: Is the MIL on before or after the fault happens?
2: Is the engine at normal temperature?
3: Has the fault just happened?
This vehicle may be flash readable, I have the info for doing it, should you want it.
ACS Diagnostics acs@freeuk.com
Richard
January 2009
Automatic Answer
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