Engine check light caused by P0441 code

Congrats on putting up a post that isn't hostile and profane.

Don't be too impressed, he needs something now.

I take it that neither of you know anything about codes causing the engine check light to go on?

Well, take it how you like. But, I guess just because you're a condescending unhelpful asshole to everyone on this board doesn't mean I should be. P0441 means incorrect purge flow, and that code as a stand-alone usually points to a problem with the EVAP vsv located on the top of the engine inbetween the banks. It's the one that duty cycles when the engine is warm (I think it's orange). I say usually because that particular evap system on your car is an obtuse nightmare, and it is often the case that non-toyota techs that haven't attended the Toyota classes have a hard time diagnosing these evap system (Toyota has a class that spends about 8-9 hours just on your specific evap system). Other problems may also include one of many cracked vacuum lines in the system as well. I can tell you, though, that ECM problems are few and far between. I've only ever seen one that I can remember. Hope this helps. And I stand by my original stemtement that you're a dick, though your pernicious prose makes me chuckle sometimes. .

I'll second the notion that ECM problems are few and far between. I was speaking with the guy responsible for checking and repairing ECMs that are returned for repair, and he said that of the thousands they get every year, only about 1 every 2 or 3 years is actually bad.

You're really rubbing it in while you've got him begging for help!

That's pretty interesting. I came across one several years ago... some sort of evap problem, I want to say it had to do with the vapor pressure sensor value in the tank. Anyway, for whatever reason it kept storing a code, and it took me several days of testing and screwing with it to finally blame the computer. Even then, the service manager (a former MDT) got involved and screwed with it himself before he believed it, then the field reps showed up to inspect it themselves before finally condeming the unit. Pretty funny considering that most of those obtuse and counter-intuitive diagnostic trees in the Factory Repair Manuals inevitably lead you to "replace ECU".

Even if I had, I would gladly leave you hanging, but no, I have not encountered this trouble code.

I've never run across a bad ECU myself, and as a DSM, I usually took a shot at fixing a problem car before calling an FTS (this was in the olden days before online and hot line help). More often, the cause was a loose or bent pin in the connector. I think the reason for so many unnecessary ECU replacements was the diagnostic trees in the factory repair manuals.

Thanks for your reply. However, I don't mind being called a dick as a dick has a USE. THat is more than I can say for some of the lefties in this ng, e.g. Unlearned Dick, Art, etc..

Well, thank you for at least replying.

No, it could not be caused by filling the tank "too full."

It could be caused by not securing the gas cap fully, or by a leaky gas cap. If the light has not turned on again, I'd go with the loos cap theory and drive happy. I agree with your mechanic, wait for the light to come on again before chasing it down.

P0441 Evaporative Emission Control System Incorrect Purge Flow

All of the codes from P0440 to P0459 are from the Evaporative Emissions Control System -- they deal in some manner with gas fumes being spewed from the gas tank into the atmosphere, or the control of those fumes within the system. In the vast majority of the cases where this faimly of codes crops up, there can be fault traced back to the operator that last filled the gas tank. Until you can remove the variable of Operator Error, I'd not even think of chasing down a mechanical failure. Once the operator error is eliminated, the mechanical failures include stuff like cracked hoses ...

HINT The cracks generally appear at the connection points.

Codes related to purge flow are not caused by a loose gas cap.

All codes from P0440 to P0459 deal with the Evaporative Emissions Control System. Most of them, while not called Loose Gas Cap, deal with the effects of an unsealed fuel system. I agree that the unsealing can come from a variety of sources, it is always safe to keep a record of the code, make sure the gas cap integrity is good, reset the system, then wait to see if the code comes back again. This is not a good strategy for any other code series that I can think of, but I see no danger in approaching the emissions control system this way. If there really is a problem witht he emissions control system, the code will reappear in short order, and the OP stated that it hasn't come back yet.

As you probably know, there is no trouble code called "Loose Gas Cap." although a loose or missing gas can cause trouble code P0440 if the problem is detected over 2 trips.

The charcoal canister absorbs and stores vapors from the fuel tank. When the engine is running, the vappors in the charcoal canister are purged and burned in the engine. Basically, P0441 - Evaporative Emission Control System Incorrect Purge Flow means that the ECU has a purge when there shouldn't be one or vice versa, probably related to the valve that controls the purge from the charcoal canister. This problem is unrelated to a loose or missing gas cap or operator error and no amount of tightening or monitoring will make it go away by itself.

I agree that the unsealing can come from a

I believe that P0441 has a 2-trip detection logic so if the condition continues, it will re-appear and if the OP does not own an OBD II scan tool, the OP would have to make another trip to wherever the codes were scanned the first time. In the mean time, the vehicle does not comply with federal evaporative emissions standards.

I'm up here in Canada. Don't know what the Canadian federal authorities think about it. Most of us in Alberta don't give a flying ph*** what comes out of Ottawa!!

Except that the OP said the code has not come back since being reset.

Yes, but the other bizillion vehicles do, and a few sneaking around out of order isn't gonna matter much.

I thought they fixed that so stuff quit coming out ...