Chasing 0455 code for months- Help!

[Bigbirney]

Hello, I am hoping someone can help. I have had 0455 fuel leak code for months. System has been smoked. Purge valve was replaced. Vent valve has been replaced twice. New gas cap. Tank was even dropped the last time. When I get out of the truck I can small gas and usually a week after leaving the shop the light is back on. The gas smells funny, so they thought maybe it was the Sams Club fuel I was using. I run 87 octane with 10% Ethanol. After last repair I have only been using top tier fuels. Anyone have any ideas? Truck is an 07 Suburban with 5.3 Flex motor.

 

[HiHoeSilver]

Hello, I am hoping someone can help. I have had 0455 fuel leak code for months. System has been smoked. Purge valve was replaced. Vent valve has been replaced twice. New gas cap. Tank was even dropped the last time. When I get out of the truck I can small gas and usually a week after leaving the shop the light is back on. The gas smells funny, so they thought maybe it was the Sams Club fuel I was using. I run 87 octane with 10% Ethanol. After last repair I have only been using top tier fuels. Anyone have any ideas? Truck is an 07 Suburban with 5.3 Flex motor.

Is it ever giving you "long" starts?

 

[Bigbirney]

No it fires up right away. Fuel pump less than 2 years old.

 

[Bigbirney]

Is it ever giving you "long" starts?

No it fires up right away. Fuel pump less than 2 years old.

 

[swathdiver]

Hello, I am hoping someone can help. I have had 0455 fuel leak code for months. System has been smoked. Purge valve was replaced. Vent valve has been replaced twice. New gas cap. Tank was even dropped the last time. When I get out of the truck I can small gas and usually a week after leaving the shop the light is back on. The gas smells funny, so they thought maybe it was the Sams Club fuel I was using. I run 87 octane with 10% Ethanol. After last repair I have only been using top tier fuels. Anyone have any ideas? Truck is an 07 Suburban with 5.3 Flex motor.

You've got a large leak somewhere. Probably a broken hose or hose connection. Could be EVAP Canister. Do the smoke test again if you have one and have the spare tire out of the way and the truck up in the air so you can see above the gas tank.

 

[Bigbirney]

You've got a large leak somewhere. Probably a broken hose or hose connection. Could be EVAP Canister. Do the smoke test again if you have one and have the spare tire out of the way and the truck up in the air so you can see above the gas tank.

The last time it was smoked, the tank was already down from the truck. The only thing that hasn't been addressed is the EVAP canister. Outside of that we are all at a loss.

 

[omandave]

My Evap canister was chalk full of crud and threw me the same code when I first acquired my 09 burb.

GM redesigned the canister and the vent hose. The new one needed a 6 inch OEM jumper wire adapter, because they changed the wire plugs too.

Solved my problem...
Good luck.

 

[Big Mama]

The canister and vent valve is an easy swap and is a common failure throwing several codes. Most replacement come with the adapter wire but make sure yours does.

 

[Bigbirney]

Thanks everyone. Was the Evap Canister. Mine was full of smelly fuel and weighed 3 times what they should. Luckily I get discount on labor because the part wasn't cheap. Hopefully no more issues. Truck is damn near new with recently updated parts.

 

[Big Mama]

Great thanks for closing the loop for the next guy

 

[Rocket Man]

Great thanks for closing the loop for the next guy

Agreed

 

[Bigbirney]

I may have spoken too soon. CEL popped on yesterday while driving, but I don't smell the fuel anymore when i get out of the truck. Time to get it scanned tonight.

 

[Doubeleive]

I may have spoken too soon. CEL popped on yesterday while driving, but I don't smell the fuel anymore when i get out of the truck. Time to get it scanned tonight.

did you replace the previous parts with oem?, my bet is one of the previous replacements failed either way, there's only so many things that go wrong with the vent system.

 

[Bigbirney]

Yes, everything was replaced with OEM as far as I know, except the EVAP cannister which was just done Thursday, it was replaced with another brand, because they were out of Delco, but it was even more expensive, which I know doesn't equate to better. I don't smell the funky fuel smell anymore when I shut it off and get out of the truck.

It's a Family shop we have used for years.

Part of me thinks now it may be the Gas cap, which we replaced first with new OEM, but the lanyard that attaches it to the truck always seems to wrap around and loosen the cap. It never seems really tight.

If it wasn't my dads old truck i would have set it on fire already.

 

[Bigbirney]

Yes, everything was replaced with OEM as far as I know, except the EVAP cannister which was just done Thursday, it was replaced with another brand, because they were out of Delco, but it was even more expensive, which I know doesn't equate to better. I don't smell the funky fuel smell anymore when I shut it off and get out of the truck.

It's a Family shop we have used for years.

Part of me thinks now it may be the Gas cap, which we replaced first with new OEM, but the lanyard that attaches it to the truck always seems to wrap around and loosen the cap. It never seems really tight.

If it wasn't my dads old truck i would have set it on fire already.

 

[Bigbirney]

Back to the shop tomorrow to check everything.

 

[dross99_si]

Is it ever giving you "long" starts?

I get long starts sometimes. Been chasing a P0442 for a while now too.
They have to be related.
Do you have an idea what it could be?

 

[HiHoeSilver]

I get long starts sometimes. Been chasing a P0442 for a while now too.
They have to be related.
Do you have an idea what it could be?

After a drive, climb right under it and see if anything is wet. I had a pinhole in a fuel line that gave me long starts because it took time to build pressure. A pinhole could also be the cause of the EVAP leak.

Is it hard to fill ever?

Have you done the typical purge solenoid, vent valve, and charcoal canister? Gas cap?

 

[dross99_si]

After a drive, climb right under it and see if anything is wet. I had a pinhole in a fuel line that gave me long starts because it took time to build pressure. A pinhole could also be the cause of the EVAP leak.

Is it hard to fill ever?

Have you done the typical purge solenoid, vent valve, and charcoal canister? Gas cap?

Yes I've done all of the above except the charcoal canister. No trouble when filling up. Never smell gas either. Perhaps it could be a pin hole. Thanks for the suggestion.