P0440 evap code on 2003 GM

[Benzadmiral]

Hey, all,

Did a search on this and came up with confirmation, but need some more detail. The "Service Engine Soon" light popped on this morning on my '03 Buick Park Avenue with 3.8L N/A engine. I've been to this rodeo before, so I hopped out and checked the gas cap. Snug! So, off to Autozone, where the code reader came up with P0440, the evap system small leak or no flow condition.

From other posts here about other cars, I see that this probably has to do with the charcoal canister and the purge or vent solenoid. My basically useless Haynes manual has a picture of the top of such a canister, but says that since 2001 the canister has been located in the rear of the vehicle, near the fuel tank.

Anybody know how I can get to it and take a look to see if the hose has cracked? Is it in the trunk, behind the carpeted liner on the fuel door side?

TIA!

 

[Rlc2500HD]

Not sure where canister is but this code can also pop up from vaccum leak at engine

 

[mechtech2]

Try clearing the codes, and see if it comes up again.
You probably fixed it with the gas cap twist.

 

[ATS-V]

I had this code in my 97. Try checking the EVAP line that runs up from the brake booster to the EVAP valve, the hose tends to get loose over time since it's not clamped. You should have a diagram under the hood.

 

[sciphi]

Check again in the engine bay. Haynes was about dead wrong for my old car.

It's likely the computer throwing a fit. Maybe you need a new gas cap. Although I can't imagine a line would rust through on an 03 that has lived its life in Louisiana.

 

[Eddie]

There is a solinoid valve that could be the cause

 

[Benzadmiral]

Originally Posted By: mechtech2
Try clearing the codes, and see if it comes up again.
You probably fixed it with the gas cap twist.

I hope so. I drove the car a couple of times yesterday, but only about five miles total. Maybe the system test runs when the car is cold? If so, it might be cleared when I start it up this morning.

I'll inspect under the hood again. This canister wouldn't be under that engine cover, would it? I'll take it off and look for the canister (there's a pic, if it can be relied on, in the Haynes book).

 

[Benzadmiral]

Originally Posted By: Rlc2500HD
Not sure where canister is but this code can also pop up from vaccum leak at engine

The printout from the code reader included that as the last of 4 probably causes. I'm hoping the list ranked these in order from most likely to least!

 

[Benzadmiral]

Update: I had a look in the engine bay for the diagram 97GTP mentioned. The setup is there under the engine cover. I can't see the canister; it seems to be tucked under the windshield washer reservoir, etc. But the lines coming off the throttle body to the purge solenoid valve, and the rubber line going toward the canister, are all intact and snug.

I'll run the car later today, and we'll see if the light comes on and stays on.

 

[Benzadmiral]

Update 2: The light stayed on until I'd driven for about 20 minutes this morning. On the second start of the day, it went out and stayed out. All is well.

(I love a car that heals itself. . . .)

 

[Drew99GT]

Same thing happened on my pops truck a while back. New gas cap and the light was off in about 3 starts.

 

[mechtech2]

Cuz U fixed it!