Are you facing failed emission tests due to incomplete OBDII monitors on your Nissan? It’s a frustrating situation many Nissan owners encounter, often after a dead battery or electrical work. The solution? Performing a Nissan Obdii Drive Cycle. This guide, based on official procedures, will walk you through the steps to reset your vehicle’s monitors and get you ready for your smog check.
Understanding OBDII Drive Cycles and Readiness Monitors
Modern vehicles like Nissan use an On-Board Diagnostic System (OBDII) to monitor engine and emission control systems. These systems run self-tests, known as “monitors,” to ensure everything is functioning correctly. For your vehicle to pass an emission or smog test, these monitors need to be in a “ready” or “complete” state.
Sometimes, these monitors become “not ready” or “incomplete.” Common causes include:
- Battery Disconnection or Failure: Disconnecting your car battery, even for a short period, can reset the monitors.
- Electrical Repairs: Work on your vehicle’s electrical system can also lead to monitor resets.
- Diagnostic Trouble Code (DTC) Clearing: If you’ve recently cleared any engine codes, the monitors will reset.
A Nissan OBDII drive cycle is a specific series of driving conditions designed to allow your vehicle to run all its onboard diagnostic checks. By completing this cycle, you give your Nissan the opportunity to reset these monitors to a “ready” status.
Nissan OBDII Drive Cycle Procedure
This drive cycle is specifically tailored for many Nissan models with GA16DE engines, commonly found in vehicles like the 1998 Nissan 200SX and Sentra. While this procedure is a helpful guide, always consult your vehicle’s repair manual for the most accurate drive cycle for your specific model and engine.
Before You Begin:
- Safety First: Perform this drive cycle in a safe location, away from heavy traffic, and where you can safely perform accelerations and decelerations.
- Check Engine Light: Ensure your “Check Engine Light” is NOT illuminated. If it is, address any underlying issues first as the drive cycle might not be effective.
- Engine Coolant Temperature (ECT): Verify your engine coolant temperature is below 122°F (50°C) before starting.
Step-by-Step Nissan Drive Cycle:
- Start-Up: Start the engine. Ensure the Engine Coolant Temperature (ECT) reaches at least 122°F (50°C).
- Warm-Up Idle: Let the engine idle until the ECT reaches a minimum of 158°F (70°C).
- Extended Idle: Continue idling for 1 minute and 30 seconds.
- Moderate Acceleration & Deceleration: Gradually accelerate to 56 mph (90 km/h). Then, completely release the accelerator pedal for at least 10 seconds.
- Steady Cruise: Accelerate again to 56 mph (90 km/h) and maintain a steady speed between 53-60 mph (85-97 km/h) for 10 minutes. Note: If this steady state driving is interrupted, you can resume, but the monitor execution time may increase.
- Deceleration to Stop: Decelerate to 0 mph and idle for 10 seconds.
- Moderate Acceleration (Repeated): Accelerate gradually in about 10 seconds. Hold the accelerator pedal as steady as possible for 20 seconds.
- Repeat Acceleration: Repeat step 7 ten times. Maintain a steady accelerator pedal during each acceleration. Do not use cruise control.
- EGR Monitor Check: Check the status of the EGR (Exhaust Gas Recirculation) monitor. Repeat Step 8 until the EGR monitor status shows “complete.”
- Minimum Operation Time: Ensure the engine has been running for at least 17 minutes before proceeding to the next step.
- Steady Cruise (Extended): Accelerate as steadily as possible to between 53-60 MPH (85-97 km/h) and cruise for 3 minutes. Crucially, hold the accelerator pedal very steady during this step. If the pedal movement is not consistent, you’ll need to repeat this step.
- Stop and Turn Off: Stop the vehicle and turn the ignition OFF.
- Monitor Status Check: Check the status of your OBDII monitors using a scan tool.
Important Notes and Tips for Success
- Transmission Type: This drive cycle is designed for both Automatic Transmission (A/T) and Manual Transmission (M/T) Nissan vehicles. For automatic transmissions, ensure you are in “D” (Drive) with Overdrive (OD) ON where applicable. For manual transmissions, follow the gear shifting guidelines provided in the original document, though these are less critical for monitor completion itself and more for smooth driving during the cycle.
- Engine Temperature: Maintaining the correct engine coolant temperature is crucial for the drive cycle to be effective.
- Steady Speed: Consistency in speed and accelerator pedal position is key, especially during the cruise steps. Avoid sudden acceleration or deceleration.
- Scan Tool is Recommended: Using an OBDII scan tool is highly recommended to monitor the status of your readiness monitors before, during, and after the drive cycle. This will help you determine if the drive cycle has been successful and which monitors are still incomplete.
- Patience is Key: It may take more than one drive cycle to complete all monitors. If some monitors are still incomplete after one cycle, repeat the procedure.
- Consult a Professional: If you are still having trouble completing the drive cycle or clearing your monitors, it’s always best to consult a qualified mechanic or Nissan dealership. There might be underlying mechanical or electrical issues preventing monitor completion.
By following these steps and tips, you should be able to successfully perform a Nissan OBDII drive cycle and get your vehicle ready for its emission test. Remember to drive safely and consult your vehicle’s specific service manual for the most accurate procedures.
