Common Symptoms
- Check Engine Light illuminated
- Engine cooling fan runs continuously or excessively
- Inaccurate engine oil temperature gauge reading showing high or maximum
- Poor cold start performance or rough idle until warmed up
- Transmission shift quality issues on vehicles with integrated powertrain control
- Reduced engine performance or hesitation during acceleration
Most Likely Root Causes
- Faulty engine oil temperature sensor
- Damaged or corroded wiring harness to oil temperature sensor
- Poor electrical connection or loose connector at oil temperature sensor
- Short to voltage in sensor circuit wiring
- Failed engine control module or powertrain control module
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Component Location
Engine oil temperature sensor is typically located in the engine block, oil pan, or oil filter housing depending on manufacturer design.
Manufacturer Notes
Some manufacturers integrate oil temperature sensing into the oil pressure sensor assembly requiring replacement of the combined unit.
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