TURBOCHARGING PRESSURE LIMITATION
VALVE (WASTEGATE)
NB: the limitation valve operates in the opposite
way to the usual fittings.
The absence of control pressure causes a
turbocharging pressure limitation.
Check that there are no leaks between the vacuum
pump and the limitation valve.
Checking calibration pressure
Fit on vehicle.
Use a dial gauge which should be positioned at the
end of the wastegate rod (as far as possible in the
wastegate axis).
An underpressure is progressively generated on the
wastegate using a manual vacuum pump.
TURBOCHARGING
Pressure adjustment
Pressure adjustment
Calibration values
Fitting on the vehicle
When checking the calibration pressure it may be
necessary to adjust the wastegate rod length (A) (if
the pressure is not within tolerance).
This adjustment is made with the turbocharger in
place.
17827S
Loosen the lock nut then loosen or tighten the
adjusting nut (B).
Validate the repair in a road test, checking the "RC0
turbocharging limiter valve" parameters and the
"turbocharging pressure" on the diagnostic tools.
12-3
Underpressure
values
120 mb
400 mb
Between 10 and 12 mm
> 450 mb
12
Rod movement
(mm)
Between 1 and 4 mm
Rod at stop
17827-1R3