Hey guys, alright 2002 wrx with 102,000 miles. Just bought it but it's become quite a project. Today I went in for the CA smog test, and failed! The car passed at 2500 rpm with no problem: HC at 73 with a max of 130. However, at idle the car bombed the test. It got a measured 202 at a max of 100. The car has aftermarket headers, catless up-pipe, stock turbo, stock (surprisingly) downpipe with the large cat, and a mid-pipe back exhaust, not sure what brand. So basically the only cat is the one on the downpipe. Car is running no codes, no CEL, runs fine. I just switched the cold air intake with a stock one, as to pass the visual inspection. Idle was at 729 and the car was plenty warm before the test. I am unsure if the car has had any electronic tuning previously, but it runs and drives great.
Any ideas what would cause this? What's my cheapest fix? I'm running out of money on this project