For 1990-2009 cars

Step | Action | Value | Yes | No
--- | --- | --- | --- | ---
1 | Check for a leaking radiator. Does the radiator leak? | 103 kPa (15 psi) | Go to Step 2 | Go to Step 3
2 | Inspect the cooling system. Is there still a loss of coolant? | -- | Go to Step 3 | System OK
3 | Check for a leaking surge tank or hose. Is there a leak in the reservoir or surge tank, or is the reservoir or surge tank hose damaged? | -- | Go to Step 4 | Go to Step 5
4 | Replace the surge tank or hose.

• | On the L36 & L67 engines, refer to Coolant Recovery Reservoir Replacement .

• | On the L47 engine, refer to Radiator Surge Tank .

Is there still a loss of coolant?

--

Go to Step 5

System OK

5 | Check for any loose or damaged radiator hoses and connections. Are any radiator hoses or hose connections damaged? | -- | Go to Step 6 | Go to Step 7
6 | Reseat the hoses and clamps. If necessary, replace the hoses and the clamps. Refer to Radiator Hose Replacement . Is there still a loss of coolant? | -- | Go to Step 7 | System OK
7 | Check for a water pump gasket leak. Is there a leak at the water pump gasket? | -- | Go to Step 8 | Go to Step 9
8 | Replace the water pump gasket.

1. On the 3.8L (L36) engine, refer to Water Pump Replacement
2. On the 3.8L (L67) engine, refer to Water Pump Replacement .

Is there still a loss of coolant?

--

Go to Step 9

System OK

9 | Check for a water pump seal leak. Is there a leak at the water pump seal? | -- | Go to Step 10 | Go to Step 11
10 | Replace the water pump.

1. On the 3.8L (L36) engine, refer to Water Pump Replacement
2. On the 3.8L (L67) engine, refer to Water Pump Replacement
3. On the L47 engine, refer to Water Pump Replacement

Is there still a loss of coolant?

--

Go to Step 11

System OK

11 | Check the surge tank cap. Is the surge tank cap damaged? | -- | Go to Step 12 | Go to Step 13
12 | Replace the surge tank cap. Replace the tank if necessary. Is there still a loss of coolant? | -- | Go to Step 13 | System OK
13 | Check the cylinder head gasket for leaks. Is the cylinder head gasket leaking? | -- | Go to Step 14 | Go to Step 15
14 | Replace the cylinder head gasket. Refer to Cylinder Head Replacement in Engine Mechanical. Is there still a loss of coolant? | -- | Go to Step 15 | System OK
15 | Check if the cylinder head bolts are tightened to specification.

• | For L36 and L67, refer to Fastener Tightening Specifications in Engine Mechanical.

• | For L47, refer to Fastener Tightening Specifications in Engine Mechanical.

Are the cylinder head bolts tightened to specifications?

--

Go to Step 17

Go to Step 16

16 | Tighten the cylinder head bolts to specifications.

• | For L36 and L67, refer to Cylinder Head Replacement in Engine Mechanical. For L47, refer to Cylinder Head Replacement in Engine Mechanical.

Is there still a loss of coolant?

--

Go to Step 17

System OK

17 | Inspect the cylinder head and cylinder block. Is the cylinder head or cylinder block cracked? | -- | Go to Step 18 | Go to Step 19
18 | Replace or resurface the cylinder head or cylinder block as necessary. Refer to Cylinder Head Replacement in Engine Mechanical. Refer to Cylinder Block Repair in Engine Mechanical. Is there still a loss of coolant? | -- | Go to Step 19 | System OK
19 | Check for a leaking heater core. Is the heater core leaking? | -- | Go to Step 20 | System OK
20 | Make the necessary repairs or replace the components as necessary in order to repair the leak. Is there still a loss of coolant? | -- | -- | System OK