Code P0455 - Evaporative Emission Leak detected
Thread Starter
Safety Car
Joined: Dec 2000
Posts: 4,166
Likes: 14
From: Orlando Fl
Code P0455 - Evaporative Emission Leak detected
My C6 with 124000 miles has been throwing this code for the past 4-5 weeks - "P0455 Evaporative Emission System Large Leak detected ECM". I am able to cancel it out and it stays out for a week or two then the engine light comes back on. Anyone know what this is specifically, is it an important code I need to pay immediate attention to (or not), and how do I fix it?
Moderator, Tech Contributor
Joined: Sep 2013
Posts: 15,561
Likes: 4,030
From: Cape Coral, Florida
There are a few causes for this DTC so one can NOT say specifically what the cause is...it takes some diagnostic skill to find the cause...can be the gas cap seal faulty, a stuck open purge or vent valve or leaking EVAP hoses...if you don't possess a smoke machine it may be hard to diagnose !!
Thread Starter
Safety Car
Joined: Dec 2000
Posts: 4,166
Likes: 14
From: Orlando Fl
There are a few causes for this DTC so one can NOT say specifically what the cause is...it takes some diagnostic skill to find the cause...can be the gas cap seal faulty, a stuck open purge or vent valve or leaking EVAP hoses...if you don't possess a smoke machine it may be hard to diagnose !!
Do you think this is something I need to get checked immediately or can I wait till I get around to it...?
Moderator, Tech Contributor
Joined: Sep 2013
Posts: 15,561
Likes: 4,030
From: Cape Coral, Florida
Nothing that will cause a driveability issues but you can replace your gas cap and see it that fixes it...the other things may be a little hard to diagnose without the right equipment !!
Burning Brakes
Joined: Sep 2018
Posts: 1,023
Likes: 172
From: Auburn Al
It's something you could do yourself. Jack the car up in back so you can get under it and look for the evap sol it will look like the one you bought to replace it one plug for the wires and two hoses and wa-LS
Drifting
Joined: Jul 2006
Posts: 1,786
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From: Charlotte N.C.
This...easy and inexpensive replacement. Can purchase from any automotive store.
Retired & lovin' it!
Joined: Mar 2005
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From: Jackson NJ
My C6 with 124000 miles has been throwing this code for the past 4-5 weeks - "P0455 Evaporative Emission System Large Leak detected ECM". I am able to cancel it out and it stays out for a week or two then the engine light comes back on. Anyone know what this is specifically, is it an important code I need to pay immediate attention to (or not), and how do I fix it?
The most common fix is replacement of the gas cap seal or the gas cap itself. Next is replacement of the vent control valve/solenoid which is located under the right rear next to the fuel tank. Cost on Rock Auto is less than $25 & it's an easy DIY fix......just jack the rear & remove right rear wheel. Hopefully one of these fixes is all you need.
Instructor
Joined: Nov 2019
Posts: 149
Likes: 28
From: Belle Isle Florida
I have an extra new gas cap you can have to try. I think you said Orlando as I am in Orlando also near the airport. I had to have my car smoke tested as I was getting P0440 quite often. They found something on top of the gas tank leaking which seemed to have fixed it. Let me kow if you want to try the gas cap.
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Here's the full story on error code P0455 - https://www.smogtips.com/smog-questi...e%20atmosphere.
The most common fix is replacement of the gas cap seal or the gas cap itself. Next is replacement of the vent control valve/solenoid which is located under the right rear next to the fuel tank. Cost on Rock Auto is less than $25 & it's an easy DIY fix......just jack the rear & remove right rear wheel. Hopefully one of these fixes is all you need.
The most common fix is replacement of the gas cap seal or the gas cap itself. Next is replacement of the vent control valve/solenoid which is located under the right rear next to the fuel tank. Cost on Rock Auto is less than $25 & it's an easy DIY fix......just jack the rear & remove right rear wheel. Hopefully one of these fixes is all you need.
