Easy one-page printout for the garage or repair shop
This summary uses the existing diagnostic information shown in full below.
The car's computer thinks there's something wrong with the sensor that checks how much oil pressure the engine has. It's like when a video game controller isn't working right, and the game doesn't know what you're trying to do.
The P0521 code indicates that the engine control module (ECM) has detected a problem with the oil pressure sensor or switch, which is not providing the expected readings.
The engine oil pressure sensor measures the oil pressure in the engine and sends this information to the engine control module (ECM). If the ECM detects that the oil pressure is outside the expected range or the sensor is not performing as expected, it triggers the P0521 code.
• Check Engine Light is on
• Oil pressure warning light is on
• Erratic oil pressure gauge readings
• Engine performance issues
• Faulty oil pressure sensor
• Low engine oil level
• Dirty or contaminated oil
• Wiring issues or poor electrical connections
• Mechanical engine problems affecting oil pressure
ECM: Engine Control Module, the computer that controls engine functions.
OBD-II: On-Board Diagnostics, a standardized system for self-diagnostics in vehicles.
• Check engine oil level and condition
• Inspect and test the oil pressure sensor
• Check wiring and connections to the sensor
• Measure actual oil pressure with a mechanical gauge
• Replace the oil pressure sensor
• Change the engine oil and filter
• Repair or replace damaged wiring or connectors
• Address any mechanical issues with the engine
• Oil pressure gauge
• Multimeter
• Wrench set
• OBD-II scanner
$100 - $250
Moderate
• Chevrolet Silverado
• GMC Sierra
• Dodge Ram
• Regular oil changes
• Use the correct oil type and viscosity
• Routine inspection of engine components
Sensor Issue
• Do not ignore the Check Engine Light
• Check oil level regularly
• Seek professional diagnosis if unsure
Repairs may be covered under the vehicle's powertrain warranty if applicable.
The P0521 code has been commonly reported in vehicles with high mileage or poor maintenance history.
Moderate – While the vehicle may still be drivable, it's important to address the issue to prevent potential engine damage.
Driving with low oil pressure can cause severe engine damage. Address this issue promptly.
• Engine at operating temperature
• Idle and various RPM ranges
The oil pressure sensor is typically located near the oil filter or on the engine block.
Q: Can I drive my car with a P0521 code?
A: It's not recommended to drive for long periods with a P0521 code as it may indicate low oil pressure, which can damage the engine.
Q: How do I know if my oil pressure sensor is bad?
A: Symptoms of a bad oil pressure sensor include erratic gauge readings, the oil pressure warning light, and the Check Engine Light.
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