Operation CHARM: Car repair manuals for everyone.

Turbocharger

Bar, Absolute Value
The charging pressure indicator in the vehicle tachometer shows charging pressure in bar absolute pressure.
Bar, Excess Pressure
Special tool 9103/2 (pressure guage) shows changing pressure in bar above atmospheric pressure.
Air Pressure at Sea Level 1 Bar (bar)0 Bar (bar)
Boost Pressure (M 44.51/52 1.75 +/- 10% at 3,000 Bar At RPM (bar @ rpm)0.75 +/- 10% at 3,000 Bar At RPM (bar @ rpm)
Boost Pressure (M 44.51)
With engine type M 44.51 the boost pressure drops after 3,000 rpm to the specified value.
1.52 +/- 0.03 at 5,800 Bar At RPM (bar @ rpm)
Boost Pressure (M 44.52)
With engine type M 44.52 the boost pressure remains constant until 5,800 rpm then drops after this value has been passed.
1.75 at 5,800 Bar At RPM (bar @ rpm)