Well all this started about two weekends ago when taking our daughter into Philly to the Wells Fargo Center to see the circus.... Stopped at a red light and while waiting I could feel an erratic idle/misfire. I could feel it through the seat base actually. I didn't say anything and as soon as we took off, just moved off idle, it smoothed out and went away. Next red light, same thing. The wife noticed it this time and asked what was up. I, of course, declined any info (haha), and said "ugh, its nothing, just a weird misfire". Well after alittle bit of highway driving it went away and didn't happen again til' later that night on the drive home. It was loading up bad at idle at stop signs/red lights and you could smell the exhaust strong, even in the car. I checked the codes the next morning using my Actron Scanner and it pulled up P0171.... System too lean (Bank 1). I cleared the codes, she drove it, and it was fine for a day or two. Then it happened again a few days later while she was driving home from work. I checked again, P0171, and now P0131.. O2 Sensor Circuit Low Volts (Bank 1, Sensor 1). Cleared codes and it was fine for a couple days. Now tonight, it did it again on her way home. Checked codes, P0131, P0171, and now, P0300.. Random/Multiple Cylinder Misfire Detected. So I had to clean the CAI anyway, so I've got the filter drying now and cleaned all the tubes/connections/etc. Had to be done anyway, regardless of all these codes. Now, after checking/searching on here, I've come to the conclusion I'm gonna have to check the driverside, front O2 sensor. I'll check it tomorrow afternoon once its cooled down some..... We'll see?!?