Aftr Emssn Inspctn,car at stop in gear shudders rpm goes very low. on 2006 Subaru Outback

Just had my car emssion inspct done . Now under load in gear the car shudders engine rpm drops to ~500 Repair Tech said State Emmsin machine wiped out engine codes and to drv 57-100 miles they will reset ?? any one heard of this ?? Thanks!

by in Nashua, NH on January 15, 2013
2 answers 1 comment
ANSWER by on January 15, 2013
scan forcodes and post so we can adv
COMMENT by on January 16, 2013
Hi the service tech who re checked it said there were " no " codes at all! I believe this is what he based this diagnosis on. I have since driven nearly 90 miles with no change so far. thanks
ANSWER by on January 20, 2013
Its a Drive-By-Wire. Unplug battery, push the brake pedal in, reconnect battery. With all accessories/AC off, let it idle for about 10 mins, turn AC on, let idle for another 10. It will let the ECU relearn your idle settings.