P0455 on a 2012 Chevrolet Traverse
EVAP Large or Gross Leak Detected
P0455 on a 2012 Chevrolet Traverse indicates evap large or gross leak detected. It usually stays drivable short-term but should be diagnosed promptly. The most common cause is missing, loose, or wrong-fit fuel cap (typically $0–$60). Confirm the root cause before replacing parts.
What does P0455 mean on a 2012 Chevrolet Traverse?
P0455 is set when the EVAP system's gross-leak monitor detects an opening approximately 0.090 inches (2.3 mm) or larger — or in many cases, no seal at all. This is the size of a missing gas cap, a disconnected hose, or a failed vent solenoid stuck open. The system cannot hold pressure or vacuum for the calibration period, so the ECM concludes a major leak.
This guide covers P0455 across the 2010-2014 Chevrolet Traverse generation — the symptoms, causes, and diagnostic steps below apply to every model year from 2010 through 2014.
Is it safe to drive a 2012 Chevrolet Traverse with P0455?
In most cases a 2012 Chevrolet Traverse stays drivable for short trips with P0455 active, but diagnose and repair it promptly. This is a low-severity code — ignoring it can lead to further damage or a failed emissions test.
What are the symptoms of P0455 on a 2012 Chevrolet Traverse?
- Check Engine Light is illuminated
- Distinct fuel smell, especially after refueling
- Fuel-cap warning message on the dashboard on some vehicles
- No drivability issue
- Vehicle will fail emissions / smog testing
What causes P0455 on a 2012 Chevrolet Traverse?
| Cause | Likelihood | Estimated repair (USD) |
|---|---|---|
| Missing, loose, or wrong-fit fuel cap Always check first. A locking gas cap from another vehicle that almost fits is a common source. | Most common | $0–$60 |
| Disconnected or split EVAP hose | Common | $30–$200 |
| EVAP vent valve stuck open (will not seal during the monitor test) | Common | $80–$350 |
| Damaged or rusted-through fuel filler neck | Occasional | $200–$700 |
| Cracked or broken EVAP charcoal canister | Occasional | $200–$600 |
| Damaged O-ring at the fuel pump assembly cover | Rare | $30–$500 |
| Rodent damage to EVAP hoses (parked vehicles) | Occasional | $30–$200 |
How to diagnose this on a 2012 Chevrolet Traverse
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Check the gas cap is present and correctly seated
Confirm the cap is the correct OEM cap for the vehicle. Many generic-fit replacement caps look identical but have slightly wrong gasket geometry. Hand-tighten to at least 3 clicks. Some vehicles flag a missing cap as P0455 within one drive cycle.
Tools: None
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Visually inspect the EVAP hoses near the canister
On most trucks and SUVs the EVAP canister sits behind the rear bumper or above the rear axle. Inspect every hose from the canister to the tank vent and to the purge solenoid. Pay particular attention to rodent damage on parked vehicles.
Tools: Floor jack and stands, Flashlight
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Smoke-test the EVAP system at low pressure
Introduce smoke at 0.5 psi through the service port. With a large leak the smoke will pour visibly from the failure point within seconds. If smoke escapes from the vent solenoid even with the solenoid commanded closed, replace the solenoid.
Tools: EVAP smoke machine
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Test the EVAP vent valve function
Disconnect the vent valve and apply 12 V — it should click and close. Hold a hand vacuum pump to one port and verify the valve holds vacuum when energized. A vent valve that does not close fully will set P0455 because the system can never seal.
Tools: 12 V test source, Hand vacuum pump
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Inspect the fuel filler neck and tank-top seals
Rust-belt vehicles often develop pinholes or seam separation in the metal portion of the fuel filler neck. Once the rust is through, the EVAP system cannot hold any vacuum. Replacement is the only fix.
Tools: Floor jack and stands, Inspection mirror
NHTSA complaints & recalls for the 2012 Chevrolet Traverse
Owner-reported safety complaints and official recalls filed with the U.S. National Highway Traffic Safety Administration for the 2012 Chevrolet Traverse. Use these to gauge how common a problem is on your specific vehicle before you start chasing Chevrolet Traverse diagnostics.
- ENGINE 115
- POWER TRAIN 46
- ELECTRONIC STABILITY CONTROL (ESC) 84
- STEERING 62
- ELECTRICAL SYSTEM 48
5 active recalls
- STRUCTURE:BODY:HATCHBACK/LIFTGATE Jun 2015
General Motors LLC (GM) is recalling certain model year 2008-2012 Buick Enclave vehicles manufactured January 3, 2007, to February 29, 2012, 2009-2012 Chevrolet Traverse vehicles manufactured July 6, 2008, to March 9, 2012, 2007-2012 GMC Acadia vehicles manufactured September 15,…
NHTSA campaign 15V415000 - SEAT BELTS May 2014
General Motors is recalling certain model year 2009-2014 Buick Enclave vehicles manufactured April 14, 2008, through May 14, 2014, Chevrolet Traverse vehicles manufactured June 6, 2008, through May 14, 2014, and GMC Acadia vehicles manufactured April 9, 2008, through May 14, 2014…
NHTSA campaign 14V266000 - AIR BAGS:SIDE/WINDOW Mar 2014
General Motors LLC (GM) is recalling certain model year 2008-2013 Buick Enclave and GMC Acadia and 2009-2013 Chevrolet Traverse and 2008-2010 Saturn Outlook vehicles. In the affected vehicles, increased resistance in the driver and passenger seat mounted side impact air bag (SIA…
NHTSA campaign 14V118000 - VISIBILITY:WINDSHIELD WIPER/WASHER:LINKAGES Apr 2012
GENERAL MOTORS (GM) IS RECALLING CERTAIN MODEL YEAR 2011-2012 CHEVROLET TRAVERSE, BUICK ENCLAVE, AND GMC ACADIA VEHICLES CURRENTLY REGISTERED IN ALASKA, COLORADO, CONNECTICUT, DELAWARE, IDAHO, ILLINOIS, INDIANA, IOWA, MAINE, MARYLAND, MASSACHUSETTS, MICHIGAN, MINNESOTA, MONTANA,…
NHTSA campaign 12V151000
How do I fix P0455 on a 2012 Chevrolet Traverse?
- Replace the fuel cap
- Replace the EVAP vent valve / vent solenoid
- Replace damaged EVAP hoses
- Replace the EVAP charcoal canister
- Replace the fuel filler neck
About the 2010-2014 Chevrolet Traverse
The 2010-2014 Chevrolet Traverse was commonly sold with the following powertrains: 3.6L V6, 2.0L Turbo I4. Common trims include L, LS, LT, RS, Premier, High Country.
How fast P0455 sets after a missing cap
Most OBD-II vehicles flag P0455 within one cold-start drive cycle after the cap is left off. Some Ford and GM vehicles will set a more specific “check fuel cap” message first and only escalate to P0455 if the issue persists across multiple drive cycles.
P0455 right after winter on a parked vehicle
Mice and rats chew EVAP hoses to nest inside the canister or near the fuel tank. If P0455 appears on a vehicle that has been parked for the winter, inspect every accessible EVAP hose for clean-edged bite marks before buying parts. This pattern is so common on rural-parked trucks that several shop forums have dedicated threads.
The cap that “fits” but doesn’t seal
A locking gas cap from a similar-vintage vehicle in the same brand family often threads on but seals against the filler neck at the wrong depth or angle. The result is repeated P0455 codes after every refuel. If the cap has been replaced and the code persists, double-check it is the exact OEM part number for this vehicle.