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For 1990-2009 cars only

Engine Overheating 3.5 V6 LX5

Step

Action

Value(s)

Yes

No

DEFINITION: The engine temperature lamp comes on and stays on, the temperature gauge shows hot or coolant overflows from the coolant recovery reservoir onto the ground while the engine is running.

1

Check for a missing or damaged radiator upper baffle and/or center air deflector.

Is the baffle or deflector missing or damaged?

--

Go to Step 8

Go to Step 2

2

Check for a loss of coolant.

Is there a loss of coolant?

--

Go to Step 3

Go to Step 4

3

Fill the system to the specified level. Refer to Loss of Coolant .

Does the engine overheat?

--

Go to Step 4

System OK

4

Check for low coolant protection. Refer to Coolant Concentration Testing .

Is the coolant to the correct correction?

--

Go to Step 5

Go to Step 8

5

Check for a loss of system pressure. Refer to Cooling System Leak Testing .

Is there a loss of system pressure?

--

Go to Step 8

Go to Step 6

6

Check for a faulty engine coolant temperature (ECT) sensor. Refer to Engine Coolant Temperature Sensor Replacement (3.5L Twin Cam V6 LX5).

Is the sensor operating properly?

--

Go to Step 7

Go to Step 8

7

Check for a cracked coolant recovery reservoir or a leaking hose. Refer to Loss of Coolant .

Is the reservoir cracked or is the hose leaking?

--

Go to Step 8

Go to Step 3

8

Repair or install new parts as necessary, then retest.

Does the engine overheat?

--

Go to Step 9

System OK

9

Check for incorrect drive belt tension. Refer to Drive Belt Replacement in Engine Mechanical.

Is the belt to the correct tension?

--

Go to Step 10

Go to Step 8

10

Correct for damaged water pump driveshaft.

Is the water pump driveshaft damaged or is the seal leaking?

--

Go to Step 8

Go to Step 11

11

Check for obstructed radiator air flow or bent radiator fins.

Is the radiator air flow obstructed?

--

Go to Step 8

Go to Step 12

12

Check for blocked cooling system passages.

Are the cooling system passages blocked?

--

Go to Step 8

Go to Step 13

13

Check for improper direction or inoperative cooling fans. Refer to Engine Coolant Fan Motor Replacement .

Are the cooling fans and the motors operating correctly?

--

Go to Step 14

Go to Step 8

14

Check the thermostat. Refer to Thermostat Diagnosis .

Is the thermostat stuck in the closed position?

--

Go to Step 15

Go to Step 16

15

Replace the thermostat. Refer to Engine Coolant Thermostat Replacement .

Does the engine overheat?

--

Go to Step 16

System OK

16

Check for faulty water pump. Refer to Water Pump Replacement .

Are the impeller blades broken or eroded?

--

Go to Step 8

Go to Step 17

17

Check the radiator cooling capacity.

Is the proper sized radiator being used on the vehicle?

--

Go to Step 3

Go to Step 18

18

Consult the current parts catalog. If necessary, replace the radiator. Refer to Radiator Replacement .

Is the repair complete?

--

System OK

--

Engine Overheating 3800 V6 L36

Step

Action

Value(s)

Yes

No

DEFINITION: The engine temperature lamp comes on and stays on, the temperature gauge shows hot or coolant overflows from the coolant recovery reservoir onto the ground while the engine is running.

1

Check for a loss of coolant.

Has there been a loss of coolant?

--

Go to Step 2

Go to Step 3

2

Refer to Loss of Coolant .

Does the engine still overheat?

--

Go to Step 3

System OK

3

Check for a loss of system pressure.

    • J 24460-01.
    • Refer to Cooling System Leak Testing .

Has there been a loss of system pressure?

--

Go to Step 4

Go to Step 5

4

Correct the system pressure.

Does the engine still overheat?

--

Go to Step 5

System OK

5

    • Check for low coolant protection.
    • Ensure that the solution is at the specified temperature.

Is there low coolant protection?

--

Go to Step 6

Go to Step 7

6

Correct as necessary.

Does the engine still overheat?

--

Go to Step 7

System OK

7

    • Check the drive belt tension. Refer to Drive Belt Diagnosis in Engine Mechanical.
    • Check the tensioner.

Is the tensioner working properly and the tension correct?

--

Go to Step 9

Go to Step 8

8

Replace the tensioner as necessary.

Refer to Drive Belt Tensioner Replacement in Engine Mechanical.

Does the engine still overheat?

--

Go to Step 9

System OK

9

Check to see if the timing is retarded by a malfunctioning Powertrain Control Module (PCM).

Is the timing retarded by a malfunctioning PCM?

--

Go to Step 10

Go to Step 11

10

Correct as necessary. Refer to Powertrain Control Module Replacement/Programming in Engine Controls.

Does the engine still overheat?

--

Go to Step 11

System OK

11

Check to see if any of the radiator fins are obstructed.

Are any of radiator fins obstructed?

--

Go to Step 12

Go to Step 13

12

    • Remove or relocate any add-on parts that block air to the radiator.
    • Remove any debris from the radiator fins.

Does the engine still overheat?

--

Go to Step 13

System OK

13

Check to see if any of the cooling system passages are blocked by rust or scale.

Are any of the cooling system passages blocked by rust or scale?

--

Go to Step 14

Go to Step 15

14

    • Drain the cooling system. Refer to Cooling System Draining and Filling .Cooling Fan Motor Replacement - Electric 3800 V6 L36
    • Flush the cooling system. Refer to Flushing .

Repair as necessary.

Does the engine still overheat?

--

Go to Step 15

System OK

15

Check for a pinched or kinked coolant recovery reservoir hose.

Is the reservoir hose pinched or kinked?

--

Go to Step 16

Go to Step 17

16

Replace or reroute the hose as necessary. Refer to Coolant Recovery Reservoir Replacement .

Does the engine still overheat?

--

Go to Step 17

System OK

17

Check for an inoperative cooling fan. Refer to Electrical Diagnosis in Engine Electrical.

Are there any inoperative cooling fans?

--

Go to Step 18

Go to Step 19

18

Repair or replace the electric cooling fans as necessary. Refer to Cooling System Draining and Filling .

Does the engine still overheat?

--

Go to Step 19

System OK

19

Check for a loose, damaged, and/or missing deflector.

Are there any loose, damaged, or missing deflectors?

--

Go to Step 20

Go to Step 21

20

Replace the deflectors.

Does the engine still overheat?

--

Go to Step 21

System OK

21

Check to see if the thermostat is stuck in the closed position. Is the thermostat stuck in the closed position?

--

Go to Step 22

Go to Step 23

22

Replace the thermostat. Refer to Engine Coolant Thermostat Replacement .

Does the engine still overheat?

--

Go to Step 23

System OK

23

Check for a faulty coolant pump.

Is the coolant pump faulty?

--

Go to Step 24

Go to Step 25

24

Replace the water pump. Refer to Water Pump Replacement .

Does the engine still overheat?

--

Go to Step 25

System OK

25

Check for an incorrect radiator. Is the radiator correct?

--

System OK

Go to Step 26

26

Install the correct radiator. Refer to Radiator Replacement .

Does the engine still overheat?

--

--

System OK