Safety Warning
DIY auto repair can cause serious injury, fire, or vehicle damage. These guides are for informational purposes only. Always follow OEM torque specs, wear PPE, and consult a certified mechanic if you are unsure. You are solely responsible for your safety.
Basic Boost Pressure Control Valve Setting
The wastegate's diaphragm unit is adjusted at the factory and should therefore only be adjusted in connection with repair or change of components. After any adjustment the basic charging pressure should always be checked, see ADJUSTING BASIC CHARGING PRESSURE .
- Loosen the end piece locknut. See Fig 1 .
- Break the seal, remove the circlip and disconnect the pushrod from the operating arm. See Fig 1 .
- Move the operating arm on the boost pressure control valve towards the "Closed" position and adjust the end piece so that the pushrod can easily be installed on the operating arm's stud. See Fig 1 .
- Then screw in the end piece 3.5 turns and tighten the locknut. This gives the boost pressure control valve about 3 mm of preload. See Fig 2 .
- Carefully withdraw the pushrod and hook it on the stud of the operating arm. Install the circlip. See Fig 3 .
- Check the boost pressure, refer to CHECKING BASIC CHARGING PRESSURE - ON-ROAD (B205L/R & B235R) .
- Affix a seal to the pushrod.
NO RELATED
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When to See a Mechanic
Stop DIY work and contact a certified mechanic immediately if any of the following apply:
- • You smell fuel, burning insulation, or see smoke.
- • Brakes feel soft, pull hard to one side, or make grinding noises.
- • The engine overheats, stalls repeatedly, or misfires under load.
- • You are missing required tools, torque specs, or safe lifting equipment.
- • You are not confident in the next step or safety outcome.