P0455 Pontiac 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 Pontiac 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 Pontiac Description
What are the Possible Causes of the DTC P0455 Pontiac?
- 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 Pontiac?
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 Pontiac 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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Frequently Asked Questions about P0455 Pontiac Code
1. What does the OBDII code P0455 Pontiac indicate?
The OBDII code P0455 Pontiac indicates that the Evaporative Emission System has detected a large leak.
2. What are common symptoms of a P0455 code in a Pontiac?
Common symptoms of a P0455 code in a Pontiac may include the check engine light illuminating on the dashboard and a gasoline odor near the vehicle.
3. What are possible causes of a P0455 code in a Pontiac?
Possible causes of a P0455 code in a Pontiac include a loose or damaged gas cap, a leak in the evaporative emissions system, a faulty purge valve, or a cracked or disconnected EVAP hose.
4. How can I diagnose a P0455 code in my Pontiac?
Diagnosing a P0455 code in your Pontiac may involve visually inspecting the gas cap for tightness, checking for visible damage to EVAP system components, using a smoke machine to detect leaks, and performing a scan tool test.
5. How serious is a P0455 code in a Pontiac?
While a P0455 code in a Pontiac may not cause immediate drivability issues, it can lead to increased emissions and potential long-term engine problems if left unresolved.
6. Can I drive my Pontiac with a P0455 code?
It is generally safe to drive your Pontiac with a P0455 code, but it is recommended to address the issue promptly to prevent further damage and ensure your vehicle meets emissions standards.
7. How do I repair a P0455 code in my Pontiac?
Repairing a P0455 code in your Pontiac may involve tightening or replacing the gas cap, repairing or replacing damaged EVAP system components, testing and replacing the purge valve if necessary, and clearing the code with a scan tool.
8. How much does it cost to fix a P0455 code in a Pontiac?
The cost to fix a P0455 code in a Pontiac can vary depending on the specific cause of the issue, but it may range from a simple gas cap replacement costing around $20 to more extensive repairs costing several hundred dollars.
9. Will a P0455 code in my Pontiac affect fuel efficiency?
A P0455 code in your Pontiac may not directly affect fuel efficiency, but addressing the issue can help ensure optimal performance and fuel economy by maintaining proper emissions control.
10. Can a P0455 code in a Pontiac clear on its own?
While some codes may clear on their own after a few driving cycles if the issue is no longer present, it is recommended to diagnose and address the root cause of a P0455 code in a Pontiac to prevent it from reoccurring.
Discuss the causes and fixes for P0455 Pontiac OBDII Code
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my gas cap was loose light came on about a week ago, I tightened but the engine light came on afterwords. My gas cap has always come loose, but when I tighten it, it still works it's self loose. Should I just buy another gas cap.
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If the problem persist, the next step is to have a tech with a smog machine check for EVAP leaks.
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A new canister vent valve fixed my problem with P0455 on a Pontiac 5.3L W-Body.
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Same here after three different gas caps. I had a smoke test done and the canister vent valve was sticking "open" and causing the "large leak" code P0455 on a 5.3L W Body. These vehicles from 05-08 are notorius for the valve going bad due to the elements(rain&snow) reaching them at the position where they are mounted. New valve fixed my "check gas cap" message on my vehicle.
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Depends what the problem is. There are many components that could set the P0455 code (EVAP Control System Leak Detected Gross Leak), you should start by checking the gas cap, make sure the cap is not loose or damage.
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I had people tell me that I needed a fuel cap. my problem with code p0455 ended up being at the top of the fuel filler neck. I found at the top of the filler is an end on the neck that the fuel cap attaches to. that top has 3 tabs that attaches the end to the neck. i had 2 tabs that were broken so it was not sealing. so the simplest or common fix is not always correct.
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The P0455 code indicates a large leak in the EVAP (evaporative emissions) system, which is usually related to a loose or faulty gas cap, cracked EVAP lines, or a failing purge or vent valve.
For your 2007 Pontiac Torrent, there is no active recall specifically for code P0455 or for the EVAP system in general. However, there may be service bulletins (TSBs) that cover common EVAP issues — like faulty vent solenoids or seal problems — that dealers may know about.
Here’s what you can do:
- Check the gas cap — make sure it’s tight and the seal is not cracked.
- Inspect for cracked or disconnected hoses near the canister or purge valve.
- If the check engine light returns after clearing, a smoke test may be needed to locate the leak.
If you're concerned, you can call a GM dealer and ask them to check for any recalls using your VIN — they can see if any emissions-related service campaigns apply to your specific vehicle.
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