My 99 Boxter was delivered to me three days ago. Occasionally on start up a billow of smoke would come out of tail pipes. I thought bad AOS. Today check engine light came on, dammit. Went to Autozone the following codes came up: P0410 and P1411. Can these two codes be triggered by faulty / bad AOS / oil separator, think this is the same part, correct? Faulty gas cap? While car was idling, I removed oil cap and it was somewhat challenging to get off, felt quite a bit of vacuum. What do you guys think. Don't want to randomly put in new parts. Smoke test most efficient way to determine leak or issues? Very bummed out. Ger.