Fix VW & Audi P0171 & P0174 Codes | Smoke Test Vacuum Leaks Fast!

Getting P0171 (System Too Lean Bank 1) or P0174 (Bank 2) engine codes on your VW or Audi? These lean condition codes often point to vacuum leaks or unmetered air — and the fastest way to find the problem is with a smoke test. In this video, I’ll show you how to use a smoke machine to pinpoint hidden vacuum leaks in your intake system, PCV hoses, and more. This method works on most Volkswagen and Audi models, including the 1.8T, 2.0T, and V6 engines that are known for common air and fuel mixture issues. We’ll cover: ✔️ How a smoke test works ✔️ Where to connect it on your VW/Audi ✔️ What to look for to find the leak ✔️ How to fix the issue and clear those codes 💨 Don’t just throw parts at your car — use this proven diagnostic method to fix it right the first time. 🔧 Like this video? Subscribe for more VW & Audi troubleshooting guides, DIY repair tips, and scan tool how-tos. Drop a comment with your code or setup — I’m here to help you get it solved!