I'm not sure if this is the right place to post cel questions. I have an 09 wrx with tsudo cat-delete downpipe mated to a perrin cbe. I'm also running cobb access port 91/92 octane stage 2 map. The downpipe came with a cel-fix. The stock o2 sensor is in place, but every couple of days the check engine, traction control and cruise control lights come on. Check engine and traction control lights stay on but cruise control light blinks. I would reset the ecu and the same problem would show up again in about two days of driving. The code reads: post catalyst fuel trim system too lean bank 1.