Engine

P0298 — Engine Oil Over Temperature Condition

Severity: medium Drive with care, to a shop

What P0298 means

The control unit received a signal that engine oil temperature exceeded its limit. Oil is normally cooled by the engine cooling system and sometimes an oil cooler, and the ECU may cut power to protect the engine when it runs too hot. The cause can be real overheating or a faulty sensor or circuit.

Symptoms

  • Check Engine light on
  • High oil or engine temperature warning
  • Reduced power or limp mode
  • Oil temperature readings higher than normal
  • Signs of engine overheating

Possible causes

  1. Real oil overheating from low, old or wrong-grade oil
  2. Faulty engine oil temperature sensor
  3. Open, short or corroded wiring or connector at the sensor
  4. Cooling system fault: thermostat, fan or low coolant
  5. Clogged or failing oil cooler
  6. Mechanical engine problem causing excess friction

How to diagnose

  1. Read codes and freeze-frame data, and look for other temperature or cooling codes
  2. Check oil level, condition and that the viscosity and spec are correct
  3. Inspect the oil temperature sensor connector and wiring
  4. Compare the sensor reading on a cold engine with coolant and air temperature
  5. Check the thermostat, cooling fans and coolant level
  6. Inspect the oil cooler and lines for blockage or leaks
  7. Measure sensor resistance and reference voltage, and test the circuit for shorts and opens
  8. If overheating is confirmed, assess the engine's mechanical condition

Common fixes

  • Replace the engine oil temperature sensor
  • Repair the wiring or connector
  • Change oil and filter with the correct spec and set the proper level
  • Service the cooling system: thermostat, fan, coolant
  • Replace or flush the oil cooler

Questions and answers

What does P0298 mean?

The ECU detected engine oil temperature that is too high. It may be genuine overheating or a sensor or wiring fault.

Can I drive with code P0298?

Only for a short distance and under light load, if there are no signs of overheating. If you see a temperature warning or lose power, stop and let the engine cool.

Can I just clear P0298?

Clearing it will not fix the cause. Check oil level, cooling and the sensor first, or the code will return and the engine could be damaged.

This is general information about the code. The meaning can differ between makes and models: a scan tool and the repair manual for your car will show the exact cause.