THERMO Valve: 320i

Disconnect vacuum hoses from thermo valve and blow air through valve. Thermo valve is okay if air flow is blocked when engine coolant is below 91°F (33°C) and flows freely when coolant is above 109°F (43°C). If not, thermo valve is defective and should be replaced.

Fig 1: Schematic of BMW Transmission Controlled Spark System

Courtesy of BMW OF NORTH AMERICA, INC.