Question: 7 Bad CVT Stepper Motor Symptoms & How To Replace the Motor

A bad CVT stepper motor can cause several performance issues in your car. It’s one of the reasons your engine might become ineffective and reduce performance. Failure to address a malfunctioning CVT stepper motor can cause more harm to your vehicle.

Luckily, your car will show several symptoms indicating the defective CVT stepper motor. These symptoms include sluggish acceleration, car hesitation, check engine light, strange sounds, malfunctioned stepper motor, and car dragging forward or reverse.

So, are you suspecting that your CVT stepper motor is the cause of the engine’s poor performance? If so, this article has you covered. We’ll detail bad CVT stepper motor symptoms and how to fix them.

Answer: CVT Stepper Motor Meaning

The CVT stepper motor is a crucial component in Nissan models that use the Continuously Variable Transmission. It relies on the Transmission Control Module (TCM) signals to expand or contract.

The expansion or contraction of the stepper motor changes the ratio control valve’s position. When the ratio control valve changes position, it modifies the pulley pressure, altering the transmission ratio.

A functional stepper motor and the entire CVT allow your engine to cruise at its best RPM. It also ensures the engine efficiently works while accelerating or changing gears.

In case of problems with the transmission ratio, your vehicle’s computer will receive P1777 or P1778 trouble codes. You’ll also see the check engine light popping on the dash to indicate issues with the transmission.

Question: Symptoms of a Bad CVT Stepper Motor

Below are tell-tale signs of a bad CVT stepper motor.

Sluggish Acceleration

Does your Nissan feel sluggish while accelerating? While several reasons can cause acceleration issues in your car, a bad CVT stepper motor could be the cause. The vehicle will accelerate slower than expected, especially when driving uphill.

Sluggish acceleration is not only annoying but can also be dangerous on busy highways. If you notice slow acceleration, park the vehicle and address the root cause.

Car Hesitation

Another noticeable symptom of a bad CVT stepper motor is your Nissan vehicle hesitating. Car hesitation means the engine takes longer to generate enough power to accelerate. The engine will stumble despite pressing the gas pedal due to insufficient power.

This issue can be uncomfortable and increase the risk of accidents on busy roads or when changing lanes. Like sluggish acceleration, park your car and troubleshoot the defective stepper motor.

Check Engine Light

The check engine light can light up on the dash to indicate your Nissan has a problem(s). If the vehicle has acceleration issues and this light pops up, a faulty CVT stepper motor could be to blame.

Further diagnosis with your OBD Scan tool might display the P1778 trouble code. This code appears when the motor fails and the CVT transmission stays at low gear.

You must repair or replace the motor to clear the check engine light. Then use your OBD scan tool to erase the P1778 error code.

Unusual Noise

Another common symptom of a defective CVT stepper motor is strange sounds emanating under the hood.

You might hear weird sounds like whining or grinding while pressing the accelerator. The strange noise can occur due to a broken stepper motor.

Like other bad CVT stepper motor symptoms, fix the defective motor before proceeding with the journey.

Car Lurching Forward or Backward

A defective stepper motor can cause your car to lurch forward or reverse when changing gears. An abrupt forward or backward movement is dangerous and can result in accidents.

Engine Overheating

If you continue driving a car with a faulty stepper motor, the engine will strain to reach its maximum RPM.

This issue causes the engine to overwork and eventually overheat. An overheated engine might cause the car to lose power and stall.

Malfunctioning Stepper Motor

You’ll need to locate the stepper motor and assess its performance to know if it’s defective. If your car has a malfunctioned stepper motor, the engine will rev, but the vehicle won’t move.

Damaged motor windings or a broken motor might cause this problem. If your stepper motor succumbs to damage, it won’t turn despite receiving sufficient current.

How to Fix a Bad CVT Stepper Motor

The best way to fix a bad stepper motor is by replacing it. However, start with the following if you notice the bad CVT stepper motor symptoms earlier:

Check the CVT Transmission Fluid

Ensure your Nissan vehicle has sufficient transmission fluid. If the fluid level is low, fill it up as required. Dirty fluid can also affect the smooth operation of the motor. Examine the fluid and replace it if it appears dirty or contaminated.

Check the Wiring

Inspect the stepper motor wiring harness to see if it’s okay. Damaged wires can stop the flow of current to the motor. Wires can also wear out and cause electrical shorts that might result in stepper motor failure.

Start by replacing any damaged or frayed wires. Then secure the wires in the harness by wrapping them with electrical tape.

Then examine the stepper motor wire connections to see if they’re tight. You can disconnect, wipe the dust on the connections and reconnect them firmly.

Clean the Stepper Motor

Dust, debris, and moisture can ruin the stepper motor, causing it to malfunction. Access the motor, remove and check if it has dust, gunk, debris, or moisture. Remove excessive dirt with a wire brush. Then use Isopropyl alcohol to clean the remaining gunk.

If the motor is moist, wipe it with a dry cloth. Then take it outside to dry naturally under the sun.

Question: How To Replace a Bad CVT Stepper Motor

If your stepper motor doesn’t work after fixing the above, you’ll need to replace it. Below we detail steps to follow when replacing a faulty CVT stepper motor.

Step 1: Turn the engine off and disconnect the battery’s negative terminal to prevent electrical shorts while replacing the motor.

Step 2: Locate the Stepper Motor. You can find this motor in the CVT transmission. Consult your car’s manual if you can’t locate the stepper motor.

Step 3: Drain the transmission fluid and remove the transmission fluid pan.

Step 4: Remove the transmission filter by screwing the three bolts holding it into place. A socket wrench will help you unscrew these bolts.

Step 5: Uninstall the valve body by removing the fasteners securing this component to your car. Then use your socket wrench to remove the bolts holding it into place. Removing the valve body will allow you to access the stepper motor.

Step 6: Remove the stepper motor by unscrewing the two bolts. Then disconnect the electrical connector from the bad stepper motor.

Step 7: Install the new stepper motor and connect the electrical connector. Ensure to install the screws and tighten them. 

Then reinstall the valve body and the transmission filter. Before reinstalling the fluid pan, clean it with a brake cleaner. Then refill it with fresh CVT transmission fluid.

Answer: Cost of Replacing a Bad CVT Stepper Motor

If you have the necessary tools, you can replace this motor yourself. You’ll find this stepper motor from third-party vendors since Nissan doesn’t supply it. The cost of this motor can range between $30 and $50. 

If a Nissan dealership fixes a faulty stepper motor, they’ll replace the whole transmission. The cost of replacing the transmission ranges between $2,000 and $4,000.

The dealership might replace the valve body and the motor instead of the entire transmission. In this case, you’ll pay between $800 and $1,000.

bad cvt stepper motor symptoms

Final Thoughts

The stepper motor is a critical component in your Nissan’s CVT transmission. It ensures the engine is effective when accelerating or changing gears. Unfortunately, the CVT stepper motor can malfunction and affect the engine’s operations.

If the motor fails, the car can have symptoms such as sluggish acceleration, check engine light, strange sounds, and car hesitation. If you notice these bad CVT stepper motor symptoms, diagnose them to determine the underlying cause. Then use our steps to replace the motor if necessary.

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