Engine Overheating (L84, L87)
Engine Overheating
| Step | Action | Yes | No | ||
|---|---|---|---|---|---|
| 1 | Inspect for a missing or damaged radiator side or upper baffle and/or radiator air deflector. Is the baffle and/or deflector missing or damaged? | Go to Step 8 | Go to Step 2 | ||
| 2 | Inspect 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. Does the engine overheat? | Go to Step 4 | System OK | ||
| 4 | Inspect for low temperature protection. Is the coolant to the correct concentration? | Go to Step 5 | Go to Step 8 | ||
| 5 | Note: Use the correct radiator surge tank cap. Inspect for a loss of cooling system pressure. Radiator Surge Tank Cap Testing Is there a loss of system pressure? | Go to Step 8 | Go to Step 6 | ||
| 6 | Inspect for a faulty engine coolant temperature (ECT) sensor. Engine Coolant Temperature Sensor Replacement Is the sensor operating properly? | Go to Step 7 | Go to Step 8 | ||
| 7 | Inspect for the following: Damaged coolant surge tank Leaking hose Bad/incorrect surge tank or radiator cap Were any of the above found? | 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 | Inspect for incorrect drive belt tension. Is the belt tension correct? | Go to Step 10 | Go to Step 8 | ||
| 10 | 1. Remove the water pump housing. Water Pump Replacement 2. Inspect for a damaged water pump shaft/hub. | Go to Step 8 | Go to Step 11 |
| Step | Action | Yes | No |
|---|---|---|---|
| Is the water pump driveshaft damaged or is the seal leaking? | |||
| 11 | Inspect for obstructed radiator air flow or bent radiator fins. Is the radiator air flow obstructed? | Go to Step 8 | Go to Step 12 |
| 12 | Inspect for blocked cooling system passages. Are the cooling system passages blocked? | Go to Step 8 | Go to Step 13 |
| 13 | Inspect the thermostat. Thermostat Diagnosis Is the thermostat stuck in the closed position? | Go to Step 15 | Go to Step 16 |
| 14 | Replace the thermostat. Water Pump Inlet Replacement Does the engine overheat? | Go to Step 16 | System OK |
| 15 | Inspect the radiator cooling capacity. Is the proper sized radiator being used on the vehicle? | Go to Step 3 | Go to Step 16 |
| 16 | Consult the current parts catalog and replace the radiator. Radiator Replacement Is the repair complete? | System OK | — |