What it means
The control module detects engine oil pressure outside the expected range. The code alone does not establish whether pressure is too high or too low.
At a glance
- Usually lights the check-engine light
How it works
The control module monitors engine oil pressure through the vehicle's pressure-sensing system and checks whether it stays within the expected operating range. P055F indicates pressure outside that range but does not specify whether it is too high or too low, and a faulty sensor can also produce a misleading reading.
Common causes
Most likely first.
- Engine oil pressure outside the calibrated range
- Oil pressure sensor or related circuit fault
Symptoms
- Check-engine light may come on
- Oil pressure warning light may come on
- Oil pressure gauge or display may show an abnormal reading
- Engine noise if oil pressure is actually too low
How to diagnose it
- Check the oil level and look for a pressure warning, abnormal gauge reading, leaks, or engine noise; shut the engine off if low pressure is indicated.
- Record freeze-frame data and observe the oil-pressure reading in live data, noting whether it is high, low, or unstable.
- Inspect the oil-pressure sensor connector and wiring for looseness, corrosion, or damage.
- Test actual oil pressure and compare it with the manufacturer's specification using the specified method.
- If actual pressure is within specification, test the sensor and its circuit against the manufacturer's specification.
Common fixes
- Correct a low oil level with the specified oil.
- Repair a loose connector or damaged sensor wiring.
- Replace a faulty oil-pressure sensor if actual pressure is normal.
- Replace a restricted oil filter or address an oil-flow restriction if confirmed.
- Repair the mechanical cause if actual oil pressure is outside specification.
Can I keep driving?
If the oil-pressure warning is on, the engine is noisy, or the gauge indicates low pressure, shut the engine off and do not drive; engine damage can happen quickly. If there are no urgent signs, minimize driving until actual oil pressure is measured.
A code shows where the control module detected a fault, not always which part failed. Check the causes in order and confirm with a test before replacing parts. Have several codes? Check them together
This is a generic code: it means the same on every make. The car’s maker may add more detail in its own service information.