I was having issues with my car above 4k rpm, but the mechanic replaced the MAF, and things were fine again. Then I had my first CEL, and took it to the garage (I forgot about the free Autozone tests), and it needed a new 02 sensor. Fine. Then I got another CEL a few weeks later for the Idle Speed Control. I wasn't having any idle problems, so I had Autozone clear the CEL. Every once in a while the idle will dip to 500 rpm and then back up, but it's rare and I haven't been concerned. Then this morning I had another CEL so I took it to Autozone again. This time it was a different idle issue and the infamous catalyst code (0420 I think). I had those erased as well. My question is, do I need to worry about these things? We don't have emissions tests here, and I'm getting fine gas mileage and other than the above mentioned idle issue running fine. I've spent $1700 on various items this year (most maintenance, but still $1700) and I don't want to spend any more money on things that don't seem to be affecting anything. FYI, I have a 2000 CSVT with 81,000 miles (I know...nice timing for the 0420 code...).
