Turbo Charger/Super charger is not following sufficient air. The vehicle does not excelerate, and slowed down in the middle of traffic. I had to turn the car off for 15 minuetes. Before i could drive home. Check engine light continues to disappear and reappear for the last 60 days. Diagnostic code P0299. GMC will not cover the cost under special coverage, known issues with 2017-2018 which GMC has special coverage.