LEMON Manuals: Even more car manuals for everyone: 1960-2025
Home >> BMW >> 1978 >> 630CSi Automatic Trans >> Repair and Diagnosis >> Engine Performance >> Engine Control Systems >> Exhaust Gas RECIRCULATION >> Testing >> Red Switching Valve >> 630CSi, 633CSi & 733i
April 5, 2026: LEMON Manuals is launched! Read the announcement.

630CSi, 633CSi & 733i

With engine off and coolant temperature above 113°F (45°C), disconnect Red hose from Red switching valve and blow air into hose. Valve is good if air flows with ignition off and does not flow with ignition on.