Step | Action | Value | Yes | No |
|---|---|---|---|---|
1 | Check for a loss of coolant. Is there a loss of coolant? | -- | ||
2 |
Does the engine overheat? | -- | System OK | |
3 | Check for a faulty engine coolant temperature (ECT) sensor. Is the sensor operating properly? | -- | ||
4 | Check for a loss of system pressure, refer to Radiator Leak Testing (On and Off Vehicle) . Is there a loss of system pressure? | -- | ||
5 | Check for a low coolant concentration level, refer to Coolant . Is the coolant concentration low? | -- | ||
6 | Repair or install new parts as necessary, then retest. Does the engine overheat? | -- | System OK | |
7 | Check for incorrect drive belt tension, refer to Accessory Drive Tensioner Diagnosis in Engine Mechanical. Is the belt tension correct? | -- | ||
8 | Check for retarded ignition timing, refer to Section 6. Is the timing retarded? | -- | ||
9 | Check for an obstructed radiator air flow or bent fins, refer to Cooling System . Is the radiator air flow obstructed? | -- | ||
10 | Check for a pinched or leaking coolant recovery reservoir hose, refer to Coolant Recovery System . Is the reservoir hose OK? | -- | ||
11 | Check for an inoperative cooling fan, refer to Cooling System Diagnosis . Is the fan operating properly? | -- | ||
12 | Check the coolant thermostat, refer to Engine Fails To Reach Normal Operating Temperature . Is the thermostat stuck in the CLOSED position? | -- | ||
13 | Check for a faulty coolant pump, refer to Cooling System Diagnosis . Is the coolant pump operating properly? | -- | ||
14 | Check for a loose, damaged or missing air deflector. Is this system OK? | -- | ||
15 | Check the radiator cooling capacity. Is the radiator the specified one for the vehicle accessory package (including aftermarket items)? | -- | ||
16 | Does the overheating occur only when pulling a trailer? Is the trailer weight, plus the vehicle weight less than the GCWR for the vehicle? | -- | ||
17 | Does the overheating occur with prolonged idling (especially with the AC ON)? | -- | ||
18 | Instruct the owner about driving techniques which will minimize this problem. | -- | System OK |
