I’m going to show you how to make your car pass a smog test 100% of the time. This guide is especially relevant for cars newer than the year 2000, as in California, these vehicles do not require a tailpipe sniffer test. Instead, the focus is on the readiness of the computer monitors.
Understanding Emission I/M Inspection Monitors
The key to passing a smog test is ensuring that your car’s I/M (Inspection and Maintenance) monitors are ready. These monitors track various systems within your vehicle to ensure they are functioning correctly. Here’s a quick overview:
- Misfire Monitor: Checks for engine misfires.
- Fuel System Monitor: Monitors the fuel system.
- Comprehensive Components Monitor: Checks various components of the car.
- Catalyst Monitor: Ensures the catalytic converter is functioning.
- EVAP System Monitor: Checks the evaporative emissions system.
- Oxygen Sensor and Heater Monitors: Monitor the oxygen sensors and their heaters.
- EGR Monitor: Ensures the Exhaust Gas Recirculation system is working.
Before starting, make sure the check engine light is off, and all other systems are functioning.
Preparing for the Smog Test
- Cold Start: Begin with a cold start; this should be the first start of the day.
- Fuel Level: Ensure your fuel tank is between 1/4 and 3/4 full.
- Initial Idle: Let the car idle for at least 10 minutes without moving it. Do not reverse or move the car during this time.
Make sure your fuel cap is secure and the vehicle is completely stock.
Drive Cycle to Set Monitors
- Warm Up: After idling for 10 minutes, begin driving your usual route.
- Trip Meter: Reset your trip meter to zero to track your progress.
- Highway Driving: Find a long stretch of road where you can safely drive. Accelerate to above 65 mph and then decelerate to below 24 mph without using the brake. You can use the parking brake or shift to slow down.
This process helps set the EGR monitor.
Checking Monitors
- Scan the System: After your drive, use a scanner to check if the monitors are ready. Look for the Catalyst, EVAP, and EGR systems.
- Repeat if Necessary: If the EVAP system is still incomplete, give it a few more cycles by turning the car on and off and allowing it to cool in between.
Final Verification
After completing around 197 miles and multiple cycles, re-scan the vehicle. Ensure all monitors are set and the EVAP system is okay. Please not as of June 20th, 2024 the EVAP is exempt even in California but is required in Oregon.
Important Notes
- No Cheating: Do not attempt to cheat by using another vehicle or tampering with the VIN. This can result in severe fines and penalties.
- Avoid Modifications: Ensure no modifications have been made to the emissions system, as this will cause a failure.
By following these steps, you can ensure your car will pass the smog test every time. Here is the video guide of this process. If you found this guide helpful and it saved you a trip to the smog station, please subscribe for more tips.
If this drive cycle was not helpful please complete your vehicle specific drive cycle which can found HERE. You can also schedule a one on one meeting with me for addtional help HERE.
