Annoying Toyota Check Engine Light: Evap Emission 441/2/6

My sister has a low mileage 2003 Toyota Highlander V6 that has begun to have it’s check engine light turn on for evaporative emissions errors (441,442,446). I’ve read the codes using the Autozone code reader and did the battery disconnect to reset the CEL. It’s back again and she’s bugging me about it. She swears she shuts the gas cap tight. Is this something we can ignore? SUV runs fine. Gas mileage is fine. The local dealer is a bit slippery… Background info: car bought used at 30,000 from Toyota dealer. Advertise as Dealer/Toyota owned and serviced car (could be malarky from the dealer and just a off-lease/trade-in). Current mileage 40,000. Primarily city miles. I’ve seen some scuttlebutt on the web about Toyota emissions systems. Any thoughts or opinions out there? Thanks!

At this point you’re going to have to go and get the manual for diagnostic steps. There may be one problem or more than one. The procedure is repair the first in line and go from there. Do not assume the gas cap is the problem; there is more to the evap system than that.

The dealer is not being “slippery”. No one in their right mind is going to flat out tell you what the problem is without having the car in hand. More than once someone has been told something off the cuff by the dealer and the dealer then becomes the recipient of a cussing when that something does not work or someone screws something up.
Another reason is that the service dept. is in business to make a profit. It would be very easy for the dealer to spend 10 hours a day dishing out free advice and chances are overtime would kick in when the word got around town about a free diagnosis being done. Shortly, there would be no diagnosis of any sort because all of the mechanics would quit since they’re paid on flat rate and free diagnosis means no shoes for the kids.

None of this means the car is a headache. It’s a 5 year old used vehicle and things happen. Can it be ignored with no bad side affects? Probably. It’s up to you and any emissions testing station if that is a factor.

Well, here are the definitions of the codes:

P0441 - Evaporative Emission Control System Incorrect Purge Flow
P0442 - Evaporative Emission Control System Leak Detected (small leak)
P0446 - Evaporative Emission Control Sytem Vent Control Circuit

Based on my experience, the problem is in the purge control circuit under the hood, and includes the line running from the charcoal canister to the engine, which happens to be the purge control line. To accurately determine the problem will require additional diagnostics. This can happen to any car. In my experience, Toyotas have not had any more problems with the evap system than any other make. Since your only solution so far has been to tighten the gas cap and reset the codes, you may need to find a real mechanic.

OK & Busted: Thanks for the quick replies. My sister’s a bit tight on cash right now and isn’t ready to drop a few hundred for a new EVAP system that the dealer is hinting. She’ll keep her fingers crossed at her next emissions test. This is the first time I’ve run across a car that had any emissions systems problems so soon. I’m hoping it’s the open/loose fuel cap. We’ll give it one more go and hope the CEL stays off…

OK4450: The sales side of this dealer was pretty slippery. I helped my sister buy this car from the dealer. I didn’t want to buy from this dealer but my sister fell in love with the car and the other dealers didn’t have the same color/options/trimline in stock. They’re also telling her that if she doesn’t go in for their 40,000 mile service package$$$, the manufactuer’s warranty will be voided.

The bad news is, the emissions test station won’t even test it with the check engine light on. You can call them to confirm this statement.
It will cost less if the SUV is taken to an independent shop.

Your sister is not required to have the car maintained by the Toyota dealer to keep the warranty in effect so that statement by them is bogus. She can have anyone service the car and keep the warranty valid.
However, she should maintain it at least on the schedule required by Toyota. Failure to do so could possibly mean a denial of a warranty claim later if Toyota feels the problem was caused by failure to perform a certain maintenance item on schedule. E.G., an engine problem develops and she cannot produce receipts and a log to show that the engine oil was changed on a regular basis.

About all I can recommend is that you get a manual and follow the steps for troubleshooting the evaporative system. It’s normally not too complicated but a methodical process should be used. Wild guessing here but the problem is usually a cracked rubber hose (would be unusual on a 40k miles car) or a defective purge solenoid.
Something to keep in mind here is that your sister should not be in the habit of topping off the gas tank when getting fuel as this could damage the evaporative canister. Round it up to the next dime or whatever but don’t continue to force feed gasoline into the tank until it’s near overflowing.

You should check the state of the emissions warranty. These are very long warranties mandated by the EPA. It might still be covered. According to Edmunds there is a 5 year/60000 warranty on the powertrain and a 8 year/80000 on the catalytic converter and onboard diagnostic devices. Ask the dealer to check this out with the computer records and scream at Toyota if he won’t.