Common Symptoms
- Check Engine Light illuminated
- Engine oil temperature gauge reading abnormally low or not moving
- Delayed or abnormal transmission shift points
- Poor cold start performance
- Fuel economy may be reduced
- Engine cooling fan may run continuously
Most Likely Root Causes
- Faulty engine oil temperature sensor
- Shorted wiring or connector at oil temperature sensor
- Damaged or corroded sensor connector terminals
- Short to ground in sensor signal circuit
- Failed engine control module
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Component Location
The engine oil temperature sensor is typically located in the engine block, oil pan, or oil filter housing depending on the vehicle manufacturer.
Manufacturer Notes
Some manufacturers use the oil temperature sensor signal for transmission shift strategy and engine protection algorithms during warm-up.
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