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'01 Olds Alero - EVAP problem - Getting choked out by gas fumes!

'01 Olds Alero, 2.4l, 4-cyl

Engine light came on about a month ago. Came up as an EVAP code (044x or something like that, can’t remember which) Around that time the car would fill up with gas vapors when I first started it up in the morning. In the cabin, all around the car, smells gassy. I’ve been leaving all the doors open when I start it in the morning and drive with the windows down for a few minutes to clear it out and it’s fine. If I drive for a while, stop, and restart, no gas smell. It’s just when I first start it up in the morning, or after it’s been sitting most the day. Guessing the gas fumes have to build up for a while for it to be noticeable.

Anyways, brought it to a shop this week (a Chevy dealer) to have it diagnosed. They tell me it’s the vent valve and want $170 to replace it. No way. Got an AC Delco replacement (#214-2117) for $17. So I installed the new valve in about 20 minutes today, but I’m STILL getting the gas fumes and the engine light is still on.

What am I missing here? Could the purge valve need replacement? Cracked vacuum line (though no other symptoms to indicate it)? Bring it back to the shop for them to do something with the computer or engine codes to get the vent valve working properly? Drive for a while to get the computer to cycle through and start the EVAP system working properly again?

Any thoughts greatly appreciated.

edit: the exact code is P0440. “Evap small leak/no flow condition. Probable Cause: 1. Defective or loose fuel cap 2. EVAP canister or hose cracked/not connected. 3. Purge or vent solenoid defective. Vacuum leak at engine.”

Others will know more but I believe the canister itself is filled with gas. One thing that will do it is continuing to fill the tank after the first or second click.

The evap system is not so complex, but problems like yours can be hard to diagnose. Having the exact code can help a lot. If you can, please have it re-read and post.

But, off-hand, I agree with Bing. I also think the charcoal canister is over-saturated and releasing gas fumes.

Others will know more but I believe the canister itself is filled with gas. One thing that will do it is continuing to fill the tank after the first or second click.

Possible, possible. But to be honest, I’m such a cheapskate and don’t really travel much so I never fill it with more than $20 at a time. I’ve had the car for about 2 years and this just started when the engine light came on. And in those 2 years I can count on one hand how many times I’ve filled the tank.

I’m going to run some errands now, I’ll stop to have it re-scanned and get the exact code.

the exact code is P0440. “Evap small leak/no flow condition. Probable Cause: 1. Defective or loose fuel cap 2. EVAP canister or hose cracked/not connected. 3. Purge or vent solenoid defective. 4.Vacuum leak at engine.”

@Arborguy thanks for the code. Unfortunately it’s one of those “catch all” codes, meaning it has to be properly diagnosed.

For anyone reading

http://service.gm.com/gmspo/mode6/pdf/2001/2001file2.pdf

The code doesn’t specifically indicate a leak.

If you want to continue on your own, perhaps throw a fuel filler cap at it. It’s cheap.
If that doesn’t help, pay someone to diagnose it properly.

If that doesn't help, pay someone to diagnose it properly.

I thought the Chevy dealer would at least get it right, but maybe they just didn’t give me the full story. Any how, I just took off the hose connecting the vent valve to the canister and noticed the end were cracked and dry-rotted. Just installed a new hose hoping that might fix it, but I’ll find out tomorrow morning. Will try new gas cap before bringing it back to the shop.

Locate the fuel pressure regulator on the fuel rail and remove the vacuum hose. If gas leaks out this connection the fuel pressure regulator diaphram has a leak and the regulator requires replacement.

Tester

@Arborguy the mechanic at the dealer may not have spent enough time diagnosing your car. Nobody’s perfect. You can always take it somewhere else if you don’t trust their diagnostic skills.

The most common cause of that p0440 code is cracked and rotted hoses or cracked connectors. If you found rotten hoses under the car, I think you may have found the source.

Good Luck.

@BustedKnuckles a bad sender seal will also cause that code. I’ve seen that a few times. But I agree in the sense that visually defective parts must first be replaced.

These links might be helpful for general diagnostic guidance on evap systems.

Most cars: http://www.agcoauto.com/content/news/p2_articleid/294

Chrysler and some German cars: http://www.agcoauto.com/content/news/p2_articleid/295