How to Perform the Throttle Relearn Procedure on Your Nissan Vehicle
If you’ve recently replaced the electronic throttle body on your Nissan, or the vehicle is idling rough, you may need to perform the throttle relearn procedure. This process recalibrates the throttle body so it operates smoothly and the engine idles at the proper speed.<>
The throttle relearn is necessary on many Nissan and Infiniti models that use an electronic throttle control system. Some of the most common models that require this procedure include:<>
- Nissan Altima
- Nissan Maxima
- Nissan Murano
- Nissan Pathfinder
- Nissan Rogue
- Nissan Sentra
- Nissan Titan
- Nissan Versa
- Infiniti G35/G37
- Infiniti M35/M45
- Infiniti QX56
Preparing for the Throttle Relearn
Before beginning the relearn process, make sure your vehicle meets all of the following conditions:<>
- No diagnostic trouble codes (DTCs) present: Use an OBD-II scanner to check for any trouble codes and address those issues first before the relearn.
- Battery voltage above 12.9V at idle: Check that your battery is fully charged. If the voltage is too low, the relearn will not complete.
- Engine at operating temperature between 158-203°F (70-95°C): Let your engine run until it reaches normal operating temperature.
- Transmission at operating temperature: Drive the vehicle for about 10 minutes to warm up the transmission fluid.
- Steering wheel in neutral position: Make sure the steering wheel is centered with the front wheels pointing straight ahead.
- No electrical load: Turn off all accessories including the A/C, radio, headlights, and anything else that draws power. On models with daytime running lights, turn the headlight switch to the first position.
- Stable idle speed between 500-1500 RPM: The engine should be idling smoothly in this RPM range without stalling or surging. If the idle is erratic, see the troubleshooting section at the end.
Once all of these criteria are met, you can move on to the relearn procedure itself. It’s a good idea to use a stopwatch to carefully time the steps.<>
Throttle Relearn Procedure
There are three main parts to the throttle relearn. Perform them in order as described below.<>
Procedure 1: Pedal Release Position Learning
- Make sure the accelerator pedal is fully released.
- Turn the ignition on (do not start the engine) and wait at least 2 seconds.
- Turn the ignition off and wait at least 10 seconds. You should hear the throttle body motor during this time.
- Turn the ignition on again and wait at least 2 seconds.
- Turn the ignition off again and wait at least 10 seconds. Listen for the throttle body sound.
Procedure 2: Throttle Valve Closed Position Learning
- Confirm the accelerator pedal is fully released.
- Turn the ignition on (do not start the engine).
- Immediately turn the ignition off and wait at least 10 seconds. The throttle body should make a sound as it cycles.
Procedure 3: Idle Air Volume Learning
- Make sure the accelerator pedal is fully released.
- Turn the ignition on (do not start) and wait 3 seconds.
- Quickly perform the following 5 times within 5 seconds:
- Fully depress the accelerator pedal
- Fully release the accelerator pedal
- Wait exactly 7 seconds, then fully depress the accelerator pedal.
- After about 20 seconds, the check engine light will stop flashing and remain on solid. Keep holding the pedal down.
- Within 3 seconds of the check engine light going solid, release the pedal and start the engine.
- Let the engine idle for at least 30 seconds. Rev it a couple of times and let it settle back to idle.
- If the idle remains stable under 850 RPM, the relearn was successful. If not, see the troubleshooting tips below.
Troubleshooting Rough/Surging Idle After Relearn
In some cases, the idle may still surge or remain erratic even after performing the relearn procedure. Nissan technical service bulletin NTB05-067 provides some additional troubleshooting steps:<>
- First check for any obvious vacuum leaks in hoses, the intake manifold, and ducting between the manifold and mass airflow sensor. Repair any leaks.
- Start the engine. It may be necessary to unplug up to 2 fuel injectors on a 4-cylinder or up to 3 injectors on a V6/V8 to stabilize the idle. For V-engines, avoid disconnecting all 3 injectors on the same bank.
- Once the idle settles down, turn off the engine. Reconnect the fuel injectors.
- Perform the full throttle relearn procedure again (all 3 steps listed earlier).
- Start the engine and verify the idle remains stable. Let it run for 30 seconds.
- If the idle stays smooth and under 850 RPM, the relearn is complete. If problems persist, further diagnosis may be needed to pinpoint the underlying issue (faulty throttle body, vacuum leak, etc.).
By following the preparation checklist and procedures carefully, your Nissan’s throttle body should relearn its calibration and idle properly. Always refer to a model-specific service manual or consult a professional technician if you are unsure about any of these steps.<>
Key Takeaways
- The throttle relearn procedure is often necessary after replacing the throttle body or to address rough/unstable idle issues on Nissan and Infiniti vehicles.
- Before beginning, make sure the vehicle has no check engine lights, the engine and transmission are warmed up, the battery is charged, and electrical loads are off.
- Carefully follow the 3-part relearn process, using a stopwatch to time the steps precisely.
- If idle problems persist, check for vacuum leaks. Disconnecting some fuel injectors may help stabilize the idle to complete the relearn.
- When in doubt, consult a factory service manual or have the procedure performed by a qualified technician to avoid damage to the throttle body or other components.
Performing the throttle relearn at home can save time and money compared to visiting a dealer, but it’s critical to adhere to the instructions to ensure the system is calibrated correctly. With patience and attention to detail, your Nissan’s throttle body will be relearned and the engine should idle like new.<>
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