Hello. I installed a turbo back exhaust and tuned it with Cobb AP v2. My engine was over boosting. It would shut the car to limp mode. so I switched it to the low waste gate map. It still overboost when I hit the throttle, but not as often.. I figured it's just the general map issue. never got around to a pro tune..

last week, I switched to stock exhaust and stage 0 map. Same issue! When I hit the throttle, my check engine light flashes for a second.

so what is going on? Do I need to go get a pro tune in order to solve this issue? kinda just want to drive the car stock and quiet for awhile

thanks