You were getting detonation?! That's normally from low octane gas and/or the air/fuel mixture being too lean. The air/fuel mixture actually acts as a "coolant" when sprayed into the combustion chamber. That sort of stuff makes great big holes in the engine. Not good! And they could not track that down?

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Mark _______________________________
2001 X5 4.4i topaz blue/sand Sport, complete Dinan S2 , hitch, V1, tint, BSW Stage 1, Alpine INA-W910BT
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You can't protect people from their own stupidity!
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