GM Service Manual Online
For 1990-2009 cars only

Step

Action

Value(s)

Yes

No

1

    Notice: When adding coolant, use DEX-COOL® coolant. If silicated coolant is added to the system, premature engine, heater core or radiator corrosion may result. In addition, the engine coolant will require change sooner-at 50 000 km (30,000 mi) or 24 months.

  1. Check the level of the coolant in the coolant recovery reservoir. The coolant level should be at the FULL COLD mark.
  2. Add engine coolant as necessary.

Does the engine reach normal operating temperature now?

--

System OK

Go to Step 2

2

  1. Check for a blockage in the coolant passages.
  2. Flush the cooling system or flow check the radiator. Refer to Flushing .

Does the engine reach normal operating temperature now?

--

System OK

Go to Step 3

3

  1. Check to see if the correct type of thermostat was installed.
  2. Check if the thermostat is stuck in the open position. Refer to Engine Overheating .
  3. If necessary, replace the thermostat. Refer to Engine Coolant Thermostat Replacement .

Does the engine reach normal operating temperature?

--

System OK

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