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.
2000 Volvo S40FACTORY OEM SERVICE PROCEDURE
Boost Pressure Control Valve
- Remove turbocharger control valve from air cleaner housing. Disconnect Yellow-marked hose from turbocharger control valve. Connect Manometer (999-5230) and Pressure Regulator (999-5766) to disconnected hose. Connect air supply to pressure regulator. See Fig 1.
- Remove heat shield from exhaust manifold. Turn set screw on pressure regulator clockwise until proper pressure is reached. See BOOST PRESSURE SPECIFICATION table. Use a vernier caliper to measure stroke of boost pressure control valve lever. Value represents opening of boost pressure control valve. Ensure valve is completely closed with lever in resting position. See Fig 2.CAUTION: DO NOT twist boost pressure control lever while adjusting. This may tear internal membrane and damage boost pressure control valve. Lever must be adjusted while mounted on servo.
- If pressure is not to specification, remove cotter pin holding boost pressure control lever. Loosen nut and adjust push rod as necessary until boost pressure is as specified. See BOOST PRESSURE SPECIFICATION table. Tighten nut to specification and reset pressure. Repeat pressure test until pressure is as specified.
- Remove pressure testing equipment when boost pressure control valve is properly set. Connect Yellow-marked hose at turbocharger control valve. Install heat shield on exhaust manifold. retrieve and diagnose any DTCs using scan tool.
- Test drive vehicle. Accelerate to wide open throttle to ensure proper valve function.
Factory Service Tools
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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.