Know the Symptoms of a Bad Knock Sensor

Engine detonation happens during the internal combustion process when the fuel mixture in the cylinder explodes and results in a change in the ignition timing.

This detonation is known as engine knocking and there are knock sensors that detect such vibrations and send a voltage signal to the powertrain control module.

The PCM works to alter the ignition's timing and thus helps to prevent the engine detonation and avoids serious damage to the engine.

But, as the knock sensor is an electronic device, it can malfunction at times and cause disturbances in the functioning of the engine and the car.

Here, are some of the commonly observed symptoms in a car when the knock sensor turns bad.

Engine warning light

The engine warning light glows up on your dashboard when there is any problem with the engine.

So, even when the knock sensor fails to operate then also the warning light illuminates and alerts the driver of a possible issue in the engine.

Get the engine checked by a professional as it might be some issue with the warning light.

Loud sounds

When the knock sensor starts to malfunction, there are instances of loud noises coming from the engine.

The issue of sounds should be resolved quickly, otherwise, the intensity of the sounds will just go on rising with every passing day.

The main reason for the loud noises is due to the ignition of the air-fuel mixture inside the cylinder when the knock sensor is not actively operating.

Bad fuel mileage

A bad knock sensor could also result in decreasing the fuel mileage of the car.

There is more use of the fuel than the needed proportion in the air-fuel mixture for the process of combustion.

Also, at time unused fuel drains out of the car through the exhaust outlet pipe.

Poor acceleration

While accelerating the car, if you experience slow acceleration as compared to normal conditions, then the bad knock sensor could be contributing to that.

A faulty knock sensor prevents the acceleration from being effective as it obstructs the sufficient combustion of the fuel mixture in the engine.

If along with the other symptoms, there is poor acceleration, then get the knock sensors checked by a technician.

Poor engine performance

The worst symptoms due to a bad knock sensor will occur when the engine starts to get damaged and delivers very poor performance.

Also, there can be a burning smell coming from the engine into the cabin due to serious issues in the engine.

In such case, the knock sensor must be immediately replaced or else the car will begin to continuously drag and jerk around.

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