EGR Thermo Valve

Fig. 35 Testing The Thermo Valve (Federal Only):

1. Disconnect the vacuum hoses from the thermo valve and connect a hand vacuum pump to the nipple of the thermo valve.
2. Apply vacuum and verify that when the engine is cold (coolant temperature less than 122° F (50° C)) vacuum leaks.
3. Allow the engine to warm up (coolant temperature greater than 176° F (80° C)), apply vacuum and verify that vacuum is held.
4. If it is necessary to remove the thermo valve do not apply a wrench to the resin part of the valve. Re-install the thermo valve using 3M locking sealant 4171. Torque the thermo valve to 15 - 30 ft.lbs (20 - 40 Nm).
5. Reconnect the vacuum hoses.