Engine
1. Clogged coolant passages
- Cylinder head(s) and piston(s)
- Heavy carbon buildup
2. Engine oil
- Incorrect oil level
- Incorrect oil viscosity
- Inferior oil quality
Cooling system
1. Coolant
- Low coolant level
2. Radiator
- Damaged or leaking radiator
- Faulty radiator cap
- Bent or damaged radiator fin
3. Water pump
- Damaged or faulty water pump
- Thermostat
- Thermostat stays closed
- Oil cooler
- Clogged or damaged oil cooler
- Hose(s) and pipe(s)
- Damaged hose
- Improperly connected hose
- Damaged pipe
- Improperly connected pipe
Fuel system
1. Throttle body (-ies)
- Damaged or loose throttle body joint
2. Air filter
- Clogged air filter element
Chassis
1. Brake(s)
- Dragging brake
Electrical system
1. Spark plug(s)
- Incorrect spark plug gap
- Incorrect spark plug heat range
2. Ignition system
- Faulty ECU
Over cooling
1. Thermostat
- Thermostat stays open