Trouble codes › P0521

P0521 Engine Oil Pressure Sensor/Switch "A" Range/Performance

Oil pressure

P0521 means the oil pressure reading doesn't make sense for how the engine is running; check the oil level and have real pressure tested.

The oil pressure signal doesn't match what the engine computer expects for the engine's speed and temperature, for example reading pressure with the engine off or too little at high rpm.

Can I keep driving? Yes, but get it fixed soon.

Check the oil level now. Don't keep driving if the oil light comes on or the engine ticks or knocks. Otherwise get it checked soon.

Common causes

  1. A failing oil pressure sensor
  2. The wrong oil viscosity or very old oil
  3. Low oil level
  4. Worn oil pump or engine bearings (less common, serious)
  5. On some engines (GM V8s, for example), a clogged oil pressure sensor screen or failing oil pump pickup

Symptoms

  • Oil pressure gauge reading oddly
  • Oil light on or flickering
  • Sometimes ticking from the valvetrain

Common on: Chevrolet Silverado 1500, Chevrolet Equinox, GMC Sierra 1500, Chevrolet Tahoe, Chevrolet Suburban, GMC Yukon

Known problems: Chrysler 3.6L Pentastar oil filter housing leak and oil pressure sensor · GM V8 oil pressure sensor and screen (P0521)

What to check first

  1. Check the oil level and change the oil with the viscosity your owner's manual specifies if it's due.
  2. Have real oil pressure checked with a mechanical gauge.
  3. Check for service bulletins on your engine's oil pressure sensor.
  4. If real pressure is low, don't drive it: the cause needs to be found before the engine is damaged.

What does P0521 mean on your vehicle?

The likely cause depends on your engine. iRepair researches your exact year, make, model and engine (service bulletins, recalls and owner reports) and tells you what to check first. Your first 3 questions are free.

Ask iRepair about P0521

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Related codes

General guidance for P0521 on most vehicles. Some makers use the same code a little differently; confirm in the service information for your vehicle, put safety first, and see a professional when in doubt.