The Hyundai i20 is a popular and reliable car known for its performance and durability. However, certain parts may experience issues over time like any mechanical component. One such component is the crankshaft sensor, which is crucial in properly functioning the Hyundai i20’s engine. This article will explore the common problems associated with the crankshaft sensor in a Hyundai i20, how to diagnose these problems, steps to replace the sensor, and tips to prevent future issues.

What is a crankshaft sensor?

Before delving into the problems, let’s understand what a crankshaft sensor is and its significance in the Hyundai i20. The crankshaft sensor, also known as the engine speed sensor, is responsible for monitoring the rotational speed and position of the crankshaft. It provides essential information to the engine control unit (ECU), enabling precise fuel injection timing and ignition timing adjustments.

Importance of the crankshaft sensor in a Hyundai i20

The crankshaft sensor is critical to the Hyundai i20’s engine management system. It ensures that the engine operates optimally by providing real-time data on the crankshaft’s rotational speed and position. This information allows the ECU to adjust fuel injection and ignition timing accurately, resulting in improved performance, fuel efficiency, and reduced emissions.

Common symptoms of crankshaft sensor problems

When the crankshaft sensor in a Hyundai i20 malfunction, several symptoms may arise, indicating potential issues. These symptoms include:

  1. Engine misfires or stalls: A faulty crankshaft sensor can disrupt the engine’s firing sequence, leading to misfires or even stalling while driving.
  2. Rough idling: An erratic or fluctuating idle speed may occur due to inconsistent data from the crankshaft sensor.
  3. Difficulties starting the engine: A defective crankshaft sensor can prevent the engine from starting or cause prolonged cranking before ignition.
  4. Reduced power and acceleration: A compromised crankshaft sensor can impact the engine’s performance, resulting in reduced power and sluggish acceleration.
  5. Illuminated check engine light: A malfunctioning crankshaft sensor often triggers the check engine light on the dashboard.

Diagnosing crankshaft sensor problems in a Hyundai i20

To diagnose crankshaft sensor problems in a Hyundai i20, certain steps can be followed:

  1. Scan for trouble codes: Utilize a diagnostic scanner to retrieve trouble codes stored in the ECU. Codes related to the crankshaft sensor can provide valuable insights into the issue.
  2. Check wiring and connections: Inspect the wiring harness and connectors associated with the crankshaft sensor for any damage, loose connections, or corrosion.
  3. Measure sensor output: Use a multimeter to measure the voltage output of the crankshaft sensor. Compare the readings with manufacturer specifications to determine if the sensor is functioning correctly.
  4. Perform a visual inspection: Examine the sensor itself for any physical damage or signs of wear.

Steps to replace the crankshaft sensor in a Hyundai i20

If the crankshaft sensor is found to be faulty, it is advisable to replace it promptly. Here are the general steps to replace the crankshaft sensor in a Hyundai i20:

  1. Disconnect the battery: Ensure the ignition is off and disconnect the negative terminal of the battery to prevent any electrical mishaps.
  2. Locate the sensor: Identify the location of the crankshaft sensor in the engine bay. It is typically positioned near the crankshaft pulley or flywheel.
  3. Remove necessary components: Depending on the specific model, you may need to remove certain components, such as the drive belt or engine covers, to access the sensor.
  4. Disconnect electrical connections: Carefully disconnect the electrical connections attached to the sensor.
  5. Remove the sensor: Unfasten the mounting bolts securing the sensor and gently remove it from its position.
  6. Install the new sensor: Install the new crankshaft sensor and tighten the mounting bolts securely.
  7. Reconnect electrical connections: Reconnect the electrical connections to the new sensor.
  8. Reassemble components: Put back any components or covers that were removed earlier to access the sensor.
  9. Reconnect the battery: Reconnect the negative terminal of the battery.
  10. Test the replacement: Start the engine and verify if the symptoms have been resolved.

How to prevent crankshaft sensor problems in a Hyundai i20

While some crankshaft sensor problems may occur due to wear and tear over time, there are preventive measures to minimize the likelihood of these issues. Consider the following tips:

  1. Regular maintenance: Adhere to the manufacturer’s recommended maintenance schedule to ensure all components, including the crankshaft sensor, are inspected and serviced at appropriate intervals.
  2. Use quality parts: When replacing the crankshaft sensor or any other components, opt for genuine or high-quality aftermarket parts to ensure reliability and longevity.
  3. Avoid harsh driving conditions: Minimize exposure to extreme temperatures, excessive vibrations, and rough driving conditions, as these factors can accelerate sensor wear.
  4. Keep electrical connections clean: Inspect and clean the electrical connections associated with the crankshaft sensor to prevent corrosion and poor contact.
  5. Address other engine issues promptly: Address any underlying engine issues promptly to prevent additional strain on the crankshaft sensor and related components.

Frequently Asked Questions (FAQs)

Can a faulty crankshaft sensor cause the Hyundai i20 to not start?

Yes, a faulty crankshaft sensor can prevent the Hyundai i20 from starting or cause difficulties in starting the engine.

How much does replacing the crankshaft sensor in a Hyundai i20 cost?

The cost of replacing the crankshaft sensor in a Hyundai i20 can vary depending on location, labour costs, and whether a genuine or aftermarket sensor is used. It is advisable to consult a trusted mechanic or Hyundai service centre for an accurate estimate.

Can I drive my Hyundai i20 with a malfunctioning crankshaft sensor?

Driving a Hyundai i20 with a malfunctioning crankshaft sensor is not recommended. Ignoring the issue can lead to further damage and potentially affect the overall performance and safety of the vehicle.

How long does a crankshaft sensor in a Hyundai i20 typically last?

The lifespan of a crankshaft sensor can vary depending on various factors, including driving conditions, maintenance, and sensor quality. In general, they are expected to last for several years.

Can a faulty crankshaft sensor cause poor fuel economy?

Yes, a faulty crankshaft sensor can negatively affect fuel economy in a Hyundai i20. The inaccurate data provided by the sensor can result in improper fuel injection timing, leading to decreased fuel efficiency.


Hyundai i20 spares, particularly the crankshaft sensor, play a pivotal role in efficiently functioning the vehicle’s engine management system. This essential component is responsible for maintaining optimal performance levels. However, with time, the crankshaft sensor may encounter issues resulting in various symptoms, such as engine misfires, rough idling, and difficulty starting the engine.

Swift and accurate diagnosis of these problems, coupled with the timely replacement of the faulty sensor, can effectively restore the smooth operation of Hyundai i20 vehicles. Additionally, adhering to preventive measures and implementing proper maintenance practices will help minimize crankshaft sensor-related concerns and ensure the longevity of the Hyundai i20’s engine.

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