Evaporative Emission Control System Pressure Sensor Malfunction
What does P0450 mean?
The P0450 code means the vehicle's onboard diagnostic system has detected: Evaporative Emission Control System Pressure Sensor Malfunction. This is a low severity code.
Common Symptoms
- Check Engine Light illuminated
- No noticeable drivability issues
- Failed emissions inspection
- Fuel tank pressure readings erratic on scan tool
Probable Causes (Ranked by Likelihood)
- Failed fuel tank pressure sensor (FTP) Very High
- Wiring issue in FTP sensor circuit High
- Corroded connector at the pressure sensor Moderate
- ECM fault in FTP sensor input circuit Low
Step-by-Step Diagnostic Procedure
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Use a scan tool to monitor fuel tank pressure sensor voltage -- it should read approximately 2.5V with the cap off (atmospheric pressure)
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Inspect the FTP sensor connector for corrosion or damage
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Check signal and ground wiring from the FTP sensor to the ECM for continuity
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Compare FTP sensor readings with a known-good mechanical gauge
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Replace the FTP sensor if readings are erratic or out of range
Frequently Asked Questions
Can I drive with code P0450?
Yes. The fuel tank pressure sensor monitors the EVAP system but does not affect engine operation. You will fail an emissions test with this code present.
Where is the fuel tank pressure sensor located?
The FTP sensor is typically mounted on top of the fuel tank or on the fuel pump module assembly. Access usually requires lowering the tank or removing a rear seat access panel.
How much does a fuel tank pressure sensor cost?
The sensor itself typically costs $40-$120 depending on the vehicle. Labor to access and replace the sensor can add $60-$230 due to fuel tank access requirements.