A Smoke Tester For Evap System is an essential tool for diagnosing leaks in a vehicle’s evaporative emission control (EVAP) system. This system prevents fuel vapors from escaping into the atmosphere. A leak can trigger the check engine light and lead to failed emissions tests. This guide provides a step-by-step approach to using a smoke machine for pinpointing EVAP leaks.
Choosing the Right Smoke Machine and Adapters
Before beginning the smoke test, ensure you have the necessary equipment:
- Automotive Smoke Machine: A quality smoke machine, like the AutoLine Pro Shop Series, is crucial. It should provide consistent smoke output and regulate pressure to prevent system damage.
- EVAP System Adapters: You’ll need an EVAP service port adapter or a gas cap adapter to connect the smoke machine to the EVAP system. The specific adapter depends on your vehicle’s make and model.
Connecting the Smoke Machine to the EVAP System
- Locate the EVAP Service Port: This port is usually located under the hood, often identified by a green cap.
- Connect the Adapter: Remove the cap and connect the appropriate EVAP adapter to the service port.
- Connect the Smoke Machine: Attach the smoke machine hose to the adapter.
Performing the Smoke Test
- Introduce Smoke: Turn on the smoke machine and allow it to fill the EVAP system with smoke.
- Inspect for Leaks: Use a bright flashlight, and potentially a laser pointer, to visually inspect all EVAP system components for escaping smoke. Focus on hoses, connections, and the fuel tank area. Work in a well-lit, enclosed space to better detect leaks.
Understanding EVAP System Pressure
It’s crucial to use a smoke machine that regulates pressure. EVAP systems operate at low pressure (around 12 inches of water or 0.5 PSI). Excessive pressure (above 7 PSI) can damage components.
Addressing Found Leaks
Once a leak is identified:
- Pinpoint the Source: If necessary, remove components like the rear seat or lower the fuel tank for better access.
- Replace Defective Parts: Replace all leaking components, including hoses, connectors, or even the fuel pump if necessary. Consider using OE parts or high-quality aftermarket options, especially for complex repairs. Sourcing from reputable vendors like dealerships or trusted online retailers ensures quality.
Final Steps After Repair
- Clear Diagnostic Trouble Codes (DTCs): Use a scan tool or disconnect the battery’s negative terminal to clear any stored DTCs related to the EVAP leak.
- Retest the System: Perform another smoke test to confirm the repair’s success.
- Drive Cycle: The vehicle’s computer needs to run its self-tests (monitors) to verify the system’s functionality. This might require driving for a few days or weeks.
This comprehensive guide helps you utilize a smoke tester for evap system diagnosis and repair. Remember to prioritize safety, use the correct equipment, and understand the nuances of the EVAP system to ensure a thorough and effective repair.
