P0455 2017 GMC Sierra 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 2017 GMC Sierra 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 2017 GMC Sierra Description
What are the Possible Causes of the DTC P0455 2017 GMC Sierra?
- 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 2017 GMC Sierra?
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)
What is the Cost to Diagnose the Code?
Labor: 1.0
To diagnose the P0455 2017 GMC Sierra 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.
Need more information about the P0455 2017 GMC Sierra code?
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Frequently Asked Questions about P0455 2017 GMC Sierra Code
What does the OBDII code P0455 mean on a 2017 GMC Sierra?
P0455 indicates a "Large Leak Detected" in the evaporative emission (EVAP) system, which prevents fuel vapors from escaping into the atmosphere.
What are common symptoms of code P0455 on a GMC Sierra?
Symptoms may include the check engine light turning on, a noticeable fuel odor, and possibly reduced fuel efficiency.
What causes the P0455 code on a 2017 GMC Sierra?
Common causes include a loose or damaged gas cap, cracked or disconnected EVAP hoses, a faulty purge valve, or a leak in the EVAP canister.
Can a loose gas cap trigger code P0455 on a GMC Sierra?
Yes, a loose, damaged, or missing gas cap is one of the most common causes of the P0455 code.
How can I troubleshoot the P0455 code on my GMC Sierra?
Start by checking the gas cap for tightness or damage. Then inspect EVAP system components like hoses, the purge valve, and the canister for visible leaks or cracks.
Is it safe to drive a 2017 GMC Sierra with the P0455 code?
While the vehicle is generally safe to drive, ignoring the issue can lead to reduced fuel efficiency and environmental harm due to fuel vapor leaks.
How do I fix the P0455 code on a GMC Sierra?
Repairs may include tightening or replacing the gas cap, repairing or replacing damaged EVAP hoses, or replacing a faulty purge valve or canister.
How much does it cost to repair the P0455 code on a GMC Sierra?
Costs vary but can range from $20 for a new gas cap to $200–$600 for parts and labor if other EVAP components need replacement.
Can extreme weather cause the P0455 code to appear?
Yes, extreme heat or cold can cause EVAP system components to expand, contract, or crack, potentially triggering the P0455 code.
Will clearing the P0455 code with a scanner fix the problem?
Clearing the code will turn off the check engine light temporarily, but the underlying issue must be repaired to prevent the code from returning.
Discuss the causes and fixes for P0455 2017 GMC Sierra OBDII Code
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