P0455 GMC Code - Evaporative Emission System Large Leak Detected
Quick Answer
The Engine Control Module (ECM) tests the Evaporative Emission (EVAP) system for a large leak or restrictions to the purge path in the EVAP system. Common causes include Missing or loose fuel cap, Incorrect fuel filler cap used, Fuel filler cap remains open or fails to close. Severity is Low - monitor the vehicle and repair when practical. The vehicle can usually be driven if no severe symptoms are present, but symptoms should be checked before extended driving.
- What it means
- P0455 GMC indicates Evaporative Emission System Large Leak Detected.
- Common causes
- Common causes include Missing or loose fuel cap, Incorrect fuel filler cap used, Fuel filler cap remains open or fails to close.
- Severity
- Low - monitor the vehicle and repair when practical.
- Can I drive?
- The vehicle can usually be driven if no severe symptoms are present, but symptoms should be checked before extended driving.
Code P0455 GMC Description
What are the Possible Causes of the DTC P0455 GMC?
- Missing or loose fuel cap
- Incorrect fuel filler cap used
- Fuel filler cap remains open or fails to close
- Foreign matter caught in fuel filler cap
- Leaking EVAP Canister
- Leaking EVAP System Hose
- Leaking Fuel Tank
- Faulty Fuel Tank Pressure Sensor
How to Fix the DTC P0455 GMC?
Review the 'Possible Causes' above and visually examine the corresponding wiring harness and connectors. Check for damaged components and inspect connector pins for signs of being broken, bent, pushed out, or corroded.
Code Tech Notes
There is a factory service bulletin for all the models from 2000 through 2021. The factory states that there are seven critical connections that could likely lead to this DTC being set:
1. Purge tube to purge valve (at intake manifold)
2. Purge tube to chassis EVAP line (at the rear of the engine, near transmission)
3. Chassis EVAP line to canister (at canister)
4. Fuel tank load line to canister (at canister)
5. Vent valve line to vent valve (at vent valve)
6. Fuel tank load line jumper connection (near fuel tank)
7. Fuel tank cap is closed properly (at refuel compartment)
User Submitted Video
What is the Cost to Diagnose the Code?
Labor: 1.0
To diagnose the P0455 GMC code, it typically requires 1.0 hour of labor. Rates vary by location, vehicle, and shop. Many shops charge between $80–$150 per hour; dealerships and metro areas may be higher, independents may be lower.
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Information for Specific GMC Models
- P0455 2014 GMC Sierra — Evaporative Emission System Large Leak Detected
- P0455 2015 GMC Sierra — Evaporative Emission System Large Leak Detected
- P0455 2016 GMC Sierra — Evaporative Emission System Large Leak Detected
- P0455 2017 GMC Sierra — Evaporative Emission System Large Leak Detected
- P0455 2018 GMC Sierra — Evaporative Emission System Large Leak Detected
Frequently Asked Questions about P0455 GMC Code
1. What are the common symptoms of OBDII code P0455 GMC?
- The common symptoms include the check engine light illuminating on the dashboard and the smell of fuel vapors around the vehicle.
2. What can cause the OBDII code P0455 GMC to trigger?
- The code is usually triggered by a large leak in the evaporative emission control system, such as a loose gas cap, damaged hoses, or a faulty purge valve.
3. How serious is the OBDII code P0455 GMC?
- While the code itself may not cause immediate drivability issues, it can lead to increased emissions and reduced fuel efficiency if left unresolved.
4. How do I diagnose the cause of OBDII code P0455 GMC?
- Diagnosing the issue typically involves inspecting the gas cap for tightness, checking the EVAP system hoses for leaks, and testing the purge valve and charcoal canister for proper operation.
5. Can I continue driving with OBDII code P0455 GMC?
- It is generally safe to drive with the code, but it is recommended to address the issue promptly to prevent potential environmental impact and reduced gas mileage.
6. How can I repair OBDII code P0455 GMC?
- Repair options may include tightening or replacing the gas cap, repairing damaged hoses, replacing the purge valve, or addressing any other identified leaks in the EVAP system.
7. Can a simple gas cap replacement fix OBDII code P0455 GMC?
- Yes, in many cases, a loose or faulty gas cap is the culprit behind the code, and replacing it with a new, properly sealing cap can resolve the issue.
8. What is the role of the evaporative emission system in a vehicle?
- The evaporative emission system helps control the release of fuel vapors from the fuel tank into the atmosphere, reducing pollution and improving fuel efficiency.
9. Is OBDII code P0455 GMC common in older vehicles?
- The code can occur in vehicles of any age, as issues with the EVAP system can arise due to wear and tear, as well as other factors like temperature changes and driving conditions.
10. How can I prevent OBDII code P0455 GMC from recurring?
- Regularly checking and maintaining the EVAP system components, ensuring the gas cap is securely tightened after refueling, and addressing any warning lights promptly can help prevent the code from recurring.
Discuss the causes and fixes for P0455 GMC OBDII Code
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I have changed many things that have to do with this code p0455 and the same code keeps popping out
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I have replaced the valve and hose on the rear above the spare tire and the gas cap on my 2007 chevy avalanche and p0455 keeps coming up
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