GM Service Manual Online
For 1990-2009 cars only

Step

Action

Value

Yes

No

1

Check for a stuck OPEN or missing coolant thermostat, refer to Cooling System Diagnosis .

Is the thermostat operating properly?

--

Go to Step 3

Go to Step 2

2

Install the correct replacement thermostat.

Is the repair complete?

--

System OK

--

3

Check the coolant level

Is the coolant level below the add mark?

--

Go to Step 4

System OK

4

  1. Add the coolant as necessary.
  2. Use the specified coolant concentration.
  3. Refer to Cooling System Diagnosis .

Is the concentration level according to the specification?

--

System OK

--