EVAP Fuel Vapor Temperature Sensor Performance
Diagnostic trouble code P2025 indicates that the Powertrain Control Module (PCM) has detected an irrational or out-of-range signal from the Evaporative Emissions (EVAP) fuel vapor temperature sensor. The PCM sets this code when the sensor's output voltage does not correlate with expected values based on ambient temperature and engine operating conditions.
This code primarily affects the vehicle's emissions system and will not cause drivability issues or strand you. However, it will cause the vehicle to fail an emissions test and should be addressed to ensure proper EVAP system operation.
Common symptoms
- Illuminated Check Engine Light
- Failure to pass an emissions inspection
- Slight decrease in fuel economy (rare)
- Faint fuel odor near the vehicle (rare)
- No noticeable drivability symptoms
Likely causes
- Faulty EVAP fuel vapor temperature sensor
- Damaged, corroded, or loose wiring/connector at the sensor
- Poor electrical ground connection for the sensor circuit
- Open or shorted circuit in the sensor wiring harness
- Faulty Powertrain Control Module (PCM) (rare)
What to check before replacing parts
Scan for additional codes and record freeze frame data.
Look for: Check if other EVAP or temperature-related codes are present, which might indicate a broader electrical issue or shared ground problem.
Visually inspect the EVAP fuel vapor temperature sensor and its wiring harness.
Look for: Look for frayed wires, melted insulation, corrosion in the connector pins, or a loose connection at the sensor.
Monitor the EVAP fuel vapor temperature sensor PID using a scan tool.
Look for: Compare the sensor's reading to the ambient air temperature and engine coolant temperature after a cold soak; they should be relatively close. An extreme reading (e.g., -40°F or 284°F) indicates an open or shorted circuit.
Test the sensor's resistance using a digital multimeter.
Look for: Disconnect the sensor and measure its resistance across the terminals. Compare the reading to the manufacturer's temperature-to-resistance chart. An out-of-spec reading means the sensor is faulty.
Check the reference voltage and ground at the sensor connector.
Look for: With the key on and engine off, verify that the PCM is supplying the correct reference voltage (usually 5 volts) and a solid ground. Lack of voltage or ground indicates a wiring issue between the sensor and the PCM.
This page explains the generic P2025 definition and is general reference information, not a diagnosis for your specific vehicle. Actual causes, severity, and repairs vary by make, model, engine, and mileage — always confirm with a scan tool and a qualified technician before replacing parts.
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