2003 Buick Ultra EVAP system code

[ellis479]

Hello,

I am getting a check engine light on my 2003 Buick Ultra 3.8 super charged engine. Checked with my innova 3100 OBD 11 and it shows a code PO440 EVAP system. I have checked the gas cap and the hose running from the power booster. What else should I check to fix this problem? Thanks ellis479

[HotZ28]

You should check all the vacuum lines & fittings going to and from the charcoal canister, as well as, those from the manifold to the purge solenoid. Pay particular attention to the elbow connections.

[hinton08]

The only way to truly find an EVAP leak is to take it and have it smoke tested at a repair shop. You wont be able to see if the gas cap isn't sealing more than likely. I'd get a gas cap from the parts dept at the local dealership, probably for about $20 or so. You can try getting a gas cap at Auto Zone or something but on the newer vehicles, I've seen aftermarket gas caps not fix the problems, and then get a GM gas cap and it fixes it. So i'd just fork over the extra $10-15 to get a AC Delco gas cap and not risk it. More than likely that will fix it. If for some reason it doesnt, I would take it to a dealer to have it smoke tested to pinpoint the leak. Hope that helps

[HotZ28]

Originally Posted by hinton08

The only way to truly find an EVAP leak is to take it and have it smoke tested at a repair shop. You wont be able to see if the gas cap isn't sealing more than likely. I'd get a gas cap from the parts dept at the local dealership, probably for about $20 or so. You can try getting a gas cap at Auto Zone or something but on the newer vehicles, I've seen aftermarket gas caps not fix the problems, and then get a GM gas cap and it fixes it. So i'd just fork over the extra $10-15 to get a AC Delco gas cap and not risk it. More than likely that will fix it. If for some reason it doesnt, I would take it to a dealer to have it smoke tested to pinpoint the leak. Hope that helps

The OP says:

Originally Posted by 479ellis

I have checked the gas cap and the hose running from the power booster.

One question remains, how was the the gas cap checked?

[ellis479]

Hello,

I replaced the gas cap as advised, since I could not see any cracking on the rubber lines. I reset the service engine light with my OBD tool and so far the light is staying off. Thanks for you help Hot Z28 and hinton08!!! ellis479

[hinton08]

Probably meant that they checked to make sure the gas cap was tight