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p0440 code on an 01 Camry, 6 cyl.,88051 mi.
October 3, 2010
Went to get smogged and this code, P0440, kicked out. Ck'd engine and found a few minors. Cleared code, drove 80 to 100 miles, and failed another smog due to 2 monitors not resetting. I have had it diag'd and been told I could need a new tank, or an ECM, or an o2 sensor. The tech also wants to "smoke ck" the car for leaks. Why not throw a dart? The car is a gem without any history except starting and running fine. Any experienced answers will be greatly appreciated. Thanks. TL

October 4, 2010#1
You're ONLY getting code 440? Because thats normally the "loose gas cap" code which could also indicate a leak in the evaporative emissions system (the fuel tank vapor recovery system). Leaks in that are not all that uncommon after nine years but ... could also just be a bad gas cap. Where are they getting these other sensors from? Did they fail the state test somehow though the only code showing up is 440?

(OBD II computer code list)

October 5, 2010#2
P0440 Evaporative Emission Control System Malfunction is fairly broad. Unfortunately, there are a number of possible culprits that could cause this code to be set, hence the technician's seemingly broad range of possible trouble spots.

Having a "smoke" check is not a bad idea - this sort of test can quickly pinpoint any leaks in the system and can eliminate possible culprits. As the extent of the EVAP system runs from the gas fill cap all the way to the throttle body.

The I/M readiness monitors not being set after 80-100 is also possible, as it goes on a preset number of starts/stops, engine RPMs, temperature ranges, and engine loads. Sometimes it will be set as soon as 50 miles, sometimes it can take as long as 200-250 miles. All depends on the driving conditions.

As Dave indicated, the most common cause is a loose or faulty gas cap. Sometimes that rubber gasket on the cap will not seal against the neck of the fill tube, no matter how many times you get the cap to "click". The gas cap can be pressure tested separately, this will also be checked when they do a smoke test.

Topping off the gas tank can also cause this code to pop up. If you get into a habit of topping the tank off or rounding it off to the nearest dollar amount, I would highly recommend to stop that practice. Reason being, topping off the tank can flood the vapor canister with raw fuel (fuel will be forced down the vent tube into the vapor canister). Once this canister is contaminated with raw fuel, it will be damaged and will through this code.

October 11, 2010#3
Overfilling is a good point to bring up. I've had this problem and it was expensive. Since then I've told every attendant (I live in New Jersey, home of full service) to stop immediately - not top it off. Some dont listen, which is annoying, especially since its against the state law to keep going!

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