Problem with 2004 L300-2 sedan

Do you know what code it was? I got the SES lamp on my '01 lw300 at 42K miles with code P0495 (large leak, evap canister). This is the same code you get when the gas cap is not on tight. By process of elimination, found a defective canister vent solenoid. $20 for me and free to you since you should be in warranty. Solenoid is located right behind the fuel fill and is about a 1/2 hour job to change. no problems since.

btw - hope that everybody knows that a flashing SES lamp means that there is a potential for a fire. Steady on means that the car should be drivable but needs checking soon.

The code was P0492, I think. (A small leak.) It was at the fuel neck, and they smoke tested it to make sure it was fixed.

The SES light isn't flashing, so it's okay to drive. I'll let everyone know what they find tonight. Hopefully it's nothing big.

Thanks for your help so far.

Okay, took the car in yesterday and left it there so they could take their time with it. They did another smoke test to find out if there was a leak they may have missed the first time. No leak was found, so they called Saturn's main technical service, and they told the dealership that it was most likely a faulty sensor. They ordered the part and will call me when it's in.

If this happens again, though, I'm going to be awfully upset. A car with only 1,600 miles on it shouldn't be having problems like this.

The active parts that control that are the Purge solenoid (in the engine compartment), the Vent solenoid (behind the fuel fill neck) and the canister vacuum sense (on top of the fuel tank). The first two are fairly easy to get to. The last requires half the exhaust system be removed and the tank dropped out of the vehicle :-((

The evap canister test is done when the engine is hot (and a whole list of other qualifiers). The normally open vent solenoid closes for duration of test. The Purge solenoid opens fully (normally is modulating to get a small flow). Tank vacuum sensor (similar to a MAP sensor) senses a vacuum in tank. When a certain vacuum has been achieved, both vent and purge valves are closed and the tank vacuum sensor monitors whether the vacuum is holding, is a slow leak (P0492) or large leak (P0495).

To find my fault, I disconnected the valves and controlled them with cheaters. Also added a 'T' fitting to the vapor line to monitor pressure with a gauge. In my case the large leak was a sticking vent solenoid.