Engine Check Light/P0440

[Wade Lippman]

My engine check light went on.
I took it to Autozone.
They said it was a P0440 and that a new gas cap would fix it.

I tried idling for 5 minutes with the new gas cap, but it doesn't help.
Must I give it a longer trial, or is a new gas cap an improper solution for a P0440?

I didn't find anything by doing a search here. On the general internet I found that it had to do with the fuel evaporative system, or something like that, and a gas cap might fix it.

So, what is my problem, how do I fix it, and is it something urgent.

Thanks much.

 

[Turdle]

you might try resetting the pcm by disconnecting the battery for a few minutes.
drive the car as normal, see if code stays gone ( disconnecting battery will reset code-computer)

 

[Wade Lippman]

Okay, I disconnected the battery...

I disconnected the battery and the check engine light did not come on when I started it, with the old gas cap.

I will drive it for a while and see what happens.
I am assuming that the cap wasn't put on properly at the last fill up. (the attendent did it, not me )
If the light comes back on I will disconnect the battery again and try the new gas cap.

If it comes on again after that, I will be back....

thanks much. I love user groups; I have fixed my dishwasher, refrigerator, washing machine and dryer almost for free with advice from usergroups. And now maybe my car.

 

[Wade Lippman]

Its on again!

The check engine light stayed off for about 200 miles. Then it came on again. I am assuming it is the the same code, but haven't confirmed that.

Disconnecting the battery turns it off, but I don't know for how long.
Is there something that needs to be fixed?

 

[lrlima]

I had a similiar problem. The new gas cap seemed to do the trick form me (about 2k miles so far...) Put the new one on and reset the computer. Hopefully that will work for you...

 

[Glacier991]

Often the gas cap will solve most P0455 complaints. Yours is more generic, and it is not one size fits all. This is the emissions system that captures gasoline vapors and returns them to the gas tank. I'd not worry about the light and you can drive it just fine while we exlore the possible problem. Your biggest worry will be on your next inspection - it won't pass until you fix the problem.

Do not keep disconnecting the battery. Your computer "learns your engine and car" and when you do that you make it start the process all over. Live with the light (this one ain't hurting anything) until we can get a fix. The disconnect the battery method of turning off a check engine light is not the best way.

I want to do a little further investigation but this article will educate you a little about these systems.

http://www.findarticles.com/p/articles/mi_qa3828/is_200205/ai_n9042136

 

[Wade Lippman]

I want to do a little further investigation but this article will educate you a little about these systems.

http://www.findarticles.com/p/articles/mi_qa3828/is_200205/ai_n9042136

Article's a little depressing. If it takes 300 miles to fault, the odds of finding the cause don't seem good.

Assuming there is a leak, what are the consequence?

 

[Blee1099]

check the Egr valve

 

[Glacier991]

It may take a drive cycle or two, not 300 mi. And the consequences are ..a light. THAT is all... oh and it will not pass the test. I'm still checking your situation out, hope to have some suggestions for you soon. Relax... nothing BAD is happening.

 

[ExplorerDMB]

Yup, what Glacier is saying is the truth. Nothing bad will happen to your vehicle with that code.

 

[je5]

Check evaporative emission canister and gas tank for air leaks in the vent line and vacuum hoses. I ran into this on an Astro and gas tank had to be dropped and repair done to the top where the vent connected. Talk about an elusive problem.

 

[Wade Lippman]

I now have several hundred miles on it, and the light hasn't come on again. Does that imply that if there is a leak, it is tiny and not worth the hassle to fix?
For inspection purposes I can always disconnect the battery and get it in quickly; can't I?
But then I lose the use of the "check engine light" since it will always be on.
So frustrating; any advice? Thanks.

 

[Glacier991]

Clearing the CEL with a battery disconnect is not a good idea, as it requires the computer to relearn everythign about your engine/vehicle. Also, when the CEL is cleared, it will not pass the test until a few drive cycles has passed - in other words, they will know you just cleared a code... the computer will tell them - look up code P1000.