CEL Illuminated

've had my LS for about 18 months now - it's a 2000 V8 with 97k miles. For almost as long as I've had it, the CEL will come on and then after a couple days go off (sometimes sooner or longer depending on how many times I start/stop it). There's no rhyme or reason to this - it may not come on for 3 months or it may come on once a week for a month. Last Monday, December 13, the light came on and it's been on consistenly since then. I didn't schedule an appt to have it looked at right away because I had anticipated that it would go away like it normally does. Now, with the holidays here, it's nearly impossible to get it looked at by my mechanic.

Many people have noticed that their LS will misfire and the CEL will come on, but there is absolutely no difference in the way mine is running. I previously had a Ford Escape and it did have cylinder misfire problems which caused it to jerk and shake so I'm familiar with what this would feel like. I've read that I can disconnect the positive battery cable, leave it off for 5 or 10 minutes, and then reconnect it and this will reset the codes. I'm hesitant to do this, but the thought has been on my mind recently because I'm guessing the CEL will come back on if there really is a problem. Anybody have any thoughts/suggestions?? I'd prefer to not spend the $80 at my dealership to have the code read if not 100% necessary.

The local Autozone/Advance Auto can read the code for free.

My guess would be either the fuel system has a problem (stuck vent solendoid, saturated vapor canister, etc.) or the 02 sensor(s) need replaced, or the cat(s) need replaced, or a combination.

The emissions system has a 7yr/100,000 mile standard warranty.