2.7 biturbo

["Julio C Negron" <elprofe@isla.net>]

NOW the CHARGE PRESSURE!
The air mass required to develop a specific level of torque is determined by
means of an air mass calculation and produced by controlling the charge
pressure as required...
For safety reason, the engine in the biturbo regulates the charge pressure,
and not the air mass as in the case with the 1.8-litre 4-cylinder
turbocharged engine.
The charge pressure is measure by the charge pressure sender
he motronic(ME 7.1) regulated the charge pressure of both turbocharges via
the selenoid valve for charge pressure control..
If defect occur in one of the cylinder banks(e.g. melting of the catalytic
converter or blockage of the exhaust system), a purely air mass-oriented
charging system would still try to provide the computed air mass.
This would lead to an excessively high charge pressure!!!
In any case, the charge pressure control prevents an excessively hight
charge pressure building up inside the intake system!!