Definatly check your ecu extension "black box". How old is the charger conversion?
I had the same fault (I think). If it is, you will need a new black box, or an HSK FCD instead.
The black box alters the signal to the ecu to allow your standard ecu to run increased boost. If it has malfunctioned then the ecu thinks the pressure is too high.
How does the car behave when driven? Are you getting the fuel cutting? (nasty jerky spluttering when ya floor it.) Do the warning lights come on immediatly, or after harder driving?
No none of the above. I have had the codes cleared and the problem seems to have gone away. I am keeping an eye on it however.
The warning lights have come on whilst the car has been driven slow.
The black box has been replaced with a brand new one back last year.
The black box are known to fail, i have seen a new on fitted with new kit, car did about 50 - 100 miles when the black box failed :o some last and some dont mate
I might get a diagnostic check again toward end of the week. Might have been a one off as they car is now fine.