Step  | Action  | Value(s)  | Yes  | No  | 
|---|---|---|---|---|
1  | Check the level of the coolant in the coolant recovery reservoir. Is the coolant in the reservoir at the proper level?  | --  | ||
2  | Add engine coolant as necessary. Refer to Cooling System Draining and Filling . Does the engine still fail to reach normal operating temperature?  | --  | System OK  | |
3  | Check if the thermostat bypass valve is stuck open. Is the thermostat bypass valve stuck in the open position?  | --  | ||
4  | If necessary replace the bypass valve. Does the engine still fail to reach normal operating temperature?  | --  | System OK  | |
5  | Check to see if the correct type of thermostat was installed, or if the thermostat sticks (or is stuck) in the open position. Refer to Thermostat Diagnosis . Was the incorrect thermostat installed or does the thermostat stick, or is the thermostat stuck, in the open position?  | --  | System OK  | |
6  | Replace the thermostat. Refer to Engine Coolant Thermostat Replacement . Does the engine still fail to reach normal operating temperature?  | --  | --  | System OK  |