I have read some of the other misfire code issues. Seemed like either new coil packs or having the ecu flashed fixed the issues. Here is my situation:
2006 WRX Limited with 146,000 miles.
Just in the last 6-8 months I have been having an on and off CEL problem. Originally it would throw a "Bank 1 Too Lean" about once a month. I could reset it with no issues, no rough idle, nothing. Just in the last month the car has been running great, just replaced the original clutch and now all of a sudden I am getting misfire codes. It will run great then stutter a little and throw 0301,0302,0303, and 0304. Once the CEL is on the car runs fine. As soon as I reset the codes and start driving it will die whenever I roll up to a stop sign and press in the clutch, just die out. I start it back up and it will stay on for the next stop sign but maybe the one after that it will die again when I press the clutch in. It will keep doing this maybe 10-15 times and then run fine without any CEL. Then within about 30-60 minutes of driving it will throw the misfire codes. This last time it only threw 0301,0302,and 0304.
Maintenance & Info:
Oil every 4k
Short Ram AEM with K&N Cleaned every 4k
Iridium plugs gapped to .030 done yesterday- Old plugs did have a little bit of white build up.
Clutch 5k ago
rear 02 sensor & T-Belt at 105k
front 02 sensor at 70k
I also haven't ran any exhaust from the cat back since 98k, I dont think this would be involved but you never know.
Thanks for the help, California Smog is due next month and you know they don't like those orange lights..