OBD-II code guide
P0521 Engine Oil Pressure Sensor Range or Performance
P0521 means the oil pressure sensor signal is outside the expected range for engine conditions.
What it means
The oil pressure signal may be inaccurate, unstable, or reflecting an actual pressure problem.
Common symptoms
- Oil pressure light
- Unstable oil pressure gauge
- Engine ticking
- Check engine light
- Warning at idle
Likely causes
- Low oil level
- Incorrect oil viscosity
- Faulty pressure sensor
- Wiring issue
- Engine oil pressure problem
First checks
- Check oil level and condition.
- Stop driving if the warning stays on.
- Confirm actual pressure before major repairs.
- Review recent oil change viscosity and filter.