If your car is running on only three cylinders instead of four, it could be due to a failed coil-pack, spark plug, or ignition lead on the non-firing cylinder.
Continued operation could harm the engine and catalytic converter. Promptly diagnose and repair the issue to avoid further damage and excessive vibrations.
Let’s see what the problems you can face, what the reasons are, and how you can solve the issue in your car.
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Why Is The Car Running On 3 Cylinders Instead Of 4?
The phenomenon of a car running on three cylinders instead of the standard four is not uncommon. It can be attributed to a range of underlying causes. Here are the major reasons that can cause your car to run on 3 cylinders:
Ignition System Malfunctions: Disrupted Sparks
One of the common reasons for a car running on three cylinders instead of four is an issue with the ignition system. In a petrol engine, each cylinder relies on a spark plug to ignite the air-fuel mixture and initiate combustion.
If a spark plug fails to fire or if there is a problem with the ignition lead, the cylinder may not contribute effectively to the combustion process. This disruption in the spark sequence leads to reduced power output and uneven engine operation.
Faulty Coil-Pack: Inadequate Spark Generation
A faulty coil pack can also be a culprit behind the imbalance in cylinder firing. If the coil-pack malfunctions, it can lead to insufficient or irregular sparks in one cylinder. As a result, the affected cylinder might misfire or not fire at all.
Fuel Delivery Issues: Disrupted Combustion
A clogged or malfunctioning fuel injector can lead to an inadequate fuel supply to one cylinder, causing it to misfire. Similarly, a vacuum leak in the intake manifold can disrupt the balanced distribution of the air-fuel mixture among cylinders, resulting in uneven combustion.
How To Understand Only 3 Cylinders Are Working?
To determine if only three cylinders are operating in your car’s engine, you can conduct a simple visual and auditory assessment. Here’s a concise guide:
Engine Sound and Vibration
Listen to the engine’s sound while the car is idling and running. If you notice an irregular, rough, or uneven sound accompanied by increased vibrations, it could indicate that only three cylinders are functioning. A properly balanced engine should produce a smoother and more consistent sound.
Exhaust Smoke Inspection
Pay attention to the color and thickness of the exhaust smoke. If you observe darker or denser smoke than usual, especially during acceleration, it suggests incomplete combustion in one cylinder. This can be a sign that one cylinder is not firing as it should.
Power and Performance
Reduced power and performance can indicate the involvement of only three cylinders. If you notice sluggish acceleration, a lack of responsiveness, or difficulty maintaining speed, it’s likely that one cylinder is not contributing effectively.
Engine Diagnostic Scan
For a more precise diagnosis, consider using an OBD-II scanner. These devices can read the car’s onboard diagnostic system and provide error codes related to cylinder misfires or other issues. This can help pinpoint the specific cylinder that is not operating correctly.
What Are The Risks Of Driving On 3 Cylinders?
Driving a car with only three cylinders operational can lead to various risks and potential consequences. Here are some of the major risks that I found in my research:
Reduced Power and Performance
The engine’s overall power output and performance will be significantly diminished, affecting acceleration and overall driving experience.
Engine Imbalance and Vibrations
The absence of one cylinder disrupts the engine’s balance, leading to increased vibrations and rough idling. This can affect other components and cause discomfort.
Increased Fuel Consumption
The engine compensates for the loss of power by working harder, leading to higher fuel consumption and reduced fuel efficiency.
Unburnt Fuel and Emissions
Incomplete combustion in the misfiring cylinder can lead to unburnt fuel entering the exhaust system, potentially damaging the catalytic converter and increasing emissions.
Catalytic Converter Damage
Over time, the misfiring cylinder can cause overheating and damage to the catalytic converter, resulting in costly repairs.
Long-Term Engine Damage
Uneven stress on the remaining cylinders can lead to premature wear and tear on engine components, impacting engine longevity.
Risk of Stalling
Engine instability from the misfiring cylinder can increase the likelihood of stalling, especially at low speeds or idling.
Reliability Concerns
Continued driving with a cylinder not firing increases the risk of unexpected breakdowns and reduces the overall reliability of the vehicle.
What To Do When The Car Is Running On 3 Cylinders Instead Of 4?
Here’s a concise table outlining the steps to take when your car is running on three cylinders instead of four:
| Action Steps | Description |
| Listen and Observe | Pay attention to engine sound, vibrations, and exhaust smoke for signs of uneven operation. |
| Check Ignition System | Inspect spark plugs, ignition leads, and coil-packs for any damage or malfunction. |
| Examine Fuel Delivery | Ensure fuel injectors are clean and functioning correctly; address any clogs or issues. |
| Diagnose with OBD-II Scanner | Use a diagnostic tool to retrieve error codes and identify the specific cylinder with the issue. |
| Seek Professional Help | Consult a mechanic for a thorough diagnosis and necessary repairs to restore optimal operation. |
Conclusion
Driving a car on three cylinders instead of four can lead to diminished performance, increased fuel consumption, potential damage to components like the catalytic converter, and long-term engine issues.
Timely diagnosis and professional intervention are crucial to restore the vehicle’s optimal operation and ensure safe and efficient driving.