Turbo Control: BioPower
WARNING: This page is about a different car, the 2007 Saab 9-5 and 2006 Saab 9-5. However, it is still accessible from the selected car via links, so may be relevant.
The variant with 2.3 litre engine has a turbo pressure gauge in the main instrument unit. The turbo pressure gauge shows air mass per combustion, which reflects the approximate torque of the engine.
As the engine's torque and accordingly air mass per combustion can be higher during E85 operation, the functionality has been modified slightly. Irrespective of the particular ethanol content of the fuel, the reading of the turbo pressure gauge is adapted to normally show maximum reading when the engine's air mass per combustion has reached the maximum value.