P0440 and Check Gas Cap

[ironoxide]

My 02 Bonneville, at 104k, was intermittently displaying the "Check Gas Cap" message on the DIC, and then it threw the P0440 code. Right before it threw the P0440 code I detected a slight odor of gas when idling the car. I replaced the Evaporator Cannister Purge Valve/Solenoid, cost $31.95, erased the codes, and have had no further problems.

What it does: The EVAP purge valve controls the flow of vapors from the EVAP system to the intake manifold. This normally closed valve is Pulse Width Modulated (PWM) by the control module to precisely control the flow of fuel vapor to the engine. The valve will also be opened during some portions of the EVAP testing, allowing engine vacuum to enter the EVAP system.

Very easy to replace.

[swampthing]

Where did you purchase your parts, advance only has the solenoid not the purge valve

[ironoxide]

Alldata refers to the part as a valve - but when I went to NAPA Autoparts, they list it as a solenoid. Not sure why - it's a solenoid. Sorry for the confusion.

[swampthing]

thanks for the info, where is it located? on the canister?

[ironoxide]

On my '02 SLE (naturally aspirated) 3.8, it's just to the right of the coils.

1. Remove the engine shield.
2. Disconnect the electrical connector: lift tab and gently pull.
3. Disconnect vacuum hose.
4. Disconnect purge pipe.

The vacuum line and the purge pipe had different attachments to hold them in place. One was made of thin steel (sort of like butterfly wings) and I just had to move it open to allow the removal of the hose, and the other line end had to be squeezed in the right spot to misshape it to allow it to removed. Take your time - don't break anything (like I do - not this time though)!

5. Release the tab on the solenoid and remove it from the mount.

That's it. Easy. Just put the new one on in the reverse order. Then erase the code if you need to. My "Check Gas Cap" message has not been displayed in the DIC, nor has the P0440 code returned since I replaced this part. That was 3 weeks ago, and the gas cap thing was a daily annoyance.

[ironoxide]

Reporting back that the "Check Gas Cap" message has not returned, nor has the P0440 code since replacing the solenoid. I'm still getting a slight odor of gas when idling at times that I haven't been able to track down.

[brownbrentm]

I have a similar problem, I know this is an old thread, but I didnt see the need to start a new one. BUT it also seems slightly different. I dont think I have a check gas cap light, or its not coming on, I dont see one when I start the car. but I am throwing the P-0440 code. I dont smell gas, but recently (yesterday literally 10 miles after it hit 130K) it started surging during idle while I was in park, did this for about 2 or 3 minutes, then the car shut off. It hasnt surged since, but it shut off on me two or three more times after I put it in Park, could this be the same problem?

Also we have a memorial day trip to Kentucky, from Michigan, and were planning on taking this car, should we consider taking the other car, its just that is a Sunfire, and I am pushing 6'3" so not the most comfortable ride.

[Archon]

If you don't have the Digital Information Center, you won't get the display for "Check Gas Cap". The solenoid may be the problem, or it could one of several other things including the gas cap. That is not likely to be causing your stalling problem.