Which procedure is not part of the Visible Smoke Test?

Which procedure is not part of the Visible Smoke Test?

• A. Fuel Cap Pressure Test
• B. Tailpipe Smoke Test
• C. EVAP Leak Test
• D. Crankcase Smoke Test

Answer: (C)

The main idea is that the Visible Smoke Test uses smoke to reveal leaks along pathways connected to the engine’s exhaust and crankcase. By introducing smoke into the exhaust path, you can see it escaping at weak spots in the tailpipe or exhaust components, and by introducing smoke into the crankcase, you can detect leaks around seals or gaskets. This test relies on visualizing where smoke shows up to pinpoint leaks. The EVAP Leak Test, on the other hand, does not use smoke. It checks the evaporative emissions system for leaks by pressurizing or applying a vacuum and monitoring for pressure changes or vapor leaks with a different diagnostic method. Since EVAP leaks involve the fuel vapor system rather than the exhaust or crankcase pathways, they aren’t identified by visually smoke-based methods, which is why this procedure isn’t part of the Visible Smoke Test.

The main idea is that the Visible Smoke Test uses smoke to reveal leaks along pathways connected to the engine’s exhaust and crankcase. By introducing smoke into the exhaust path, you can see it escaping at weak spots in the tailpipe or exhaust components, and by introducing smoke into the crankcase, you can detect leaks around seals or gaskets. This test relies on visualizing where smoke shows up to pinpoint leaks.

The EVAP Leak Test, on the other hand, does not use smoke. It checks the evaporative emissions system for leaks by pressurizing or applying a vacuum and monitoring for pressure changes or vapor leaks with a different diagnostic method. Since EVAP leaks involve the fuel vapor system rather than the exhaust or crankcase pathways, they aren’t identified by visually smoke-based methods, which is why this procedure isn’t part of the Visible Smoke Test.