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Power too low.

Read the instructions below then start the fault diagnostic procedure.

Symptom: Loss of power

Power too low.



Fault symptoms

Loss of power

Conditions

The following conditions apply for this fault symptom:


No diagnostic trouble codes in the car with the symptom description in question.

Pedal cable adjusted correctly.

Brakes not applied.

Tyre pressures OK.

Engine compression OK.


Diagnostic help

First check that the three pressure sensors do not deviate by more than 10 kPa from each other when the engine is switched off. This check is performed because the mass air flow will later be compared with the intake pressure, which must therefore be correct. If the mass air flow does show a deviation, first check for air leaks before suspecting a fault in the mass air flow sensor.

Then check the charge air control valve, knock control function and fuel supply. Knock control is a normal engine function.

If is difficult to determine how much knocking to accept as it depends on the circumstances.

The following factors increase knocking tendency:


Low-octane fuel.

High coolant and outdoor temperatures.

High altitude.

Heavy engine load.


Diagnostic tool functions related to this fault are:


Atmosphere absolute pressure, in kPa.

Charge air absolute pressure, in kPa

Manifold absolute pressure, in kPa.

Airmass deviation from requested, in %.

Airmass deviation from calculated, in %.

Engine torque used at actual rpm, in %.

Charge air adaptation, unit %.

All readings in the ”AIR MASS REQUEST” group.

Activate charge air control valve.


See also description of readings and

activations in ”Fault diagnosis, general” for more information.