GM Service Manual Online
For 1990-2009 cars only

Step

Action

Value(s)

Yes

No

1

Check the coolant level in the radiator surge tank. Refer to Cooling System Maintenance Recommendations .

Is the coolant at the proper level?

--

Go to Step 3

Go to Step 2

2

Add coolant to the radiator surge tank as necessary.

Does the engine still fail to reach normal operating temperatures?

--

Go to Step 3

System OK

3

Check for a blockage in the coolant passages.

Are there any blockages in the coolant passages?

--

Go to Step 4

Go to Step 5

4

Flush the cooling system or flow check the radiator. Refer to Flushing .

Does the engine still fail to reach normal operating temperatures?

--

Go to Step 5

System OK

5

Check to see if the incorrect thermostat was installed or if it is stuck (or sticks) in the open position.

Was the incorrect thermostat installed, or is it stuck (or does it stick) in the open position?

--

Go to Step 6

--

6

Replace the thermostat.

    • For the 2.4L engine, refer to Engine Coolant Thermostat Replacement .
    • For the 3.1L engine, refer to Engine Coolant Thermostat Replacement

Does the engine still fail to reach normal operating temperature?

--

--

System OK