Common Symptoms
- Check Engine Light illuminated
- Erratic temperature gauge readings
- Delayed or harsh transmission shifts
- Engine cooling fan running continuously
- Poor fuel economy
Most Likely Root Causes
- Damaged or corroded wiring harness to oil temperature sensor
- Intermittent connection at sensor connector
- Failing engine oil temperature sensor
- Corroded or loose connector pins
- Damaged PCM connections
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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 vehicle application.
Manufacturer Notes
Some manufacturers use oil temperature data for transmission shift strategy and cooling fan control, so intermittent signals may affect drivability.
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