Can Bad Spark Plugs Cause Knock Sensor Code | All You Need To Know

Buying your first car can be thrilling beyond compare, but it can be seriously daunting too. Learning all the in-and-outs of your car can be challenging especially regarding engine spark plugs, but we are here to help!

One common question is always on the air, can bad spark plugs cause knock sensor code? Well in short, yes. The knock sensor checks if your engine has abnormal vibrations that the plugs could very well cause.

But many other things can cause this sensor code. What are the symptoms of the sensor code that you are getting caused by a spark plug? Or what is the first step to take if you get such a code? We shall discuss them all in the article down below.

Can Bad Spark Plugs Cause Knock Sensor Code?

The knock sensors are a device that has a sensor for checking vibrations in your engine. It displays a code to inform the user that there are abnormal vibrations inside the combustion chamber. In contrast, spark plugs in short are a device that provides a ‘spark’ to the fuel inside your car.

They are located in the inner combustion chamber of your car’s engine. They provide the necessary ‘spark’ to initiate the conversion of fuel into energy which gets your engine running.

So you must have gotten the point by now! The cause of all the major vibrations inside your car’s engine is caused by the plugs. And any abnormal vibrations could very well point to bad spark plugs.

But there are more components responsible for such a cause and we shall discuss every one of them.

Other Causes Of Knock Detection Code

As discussed above this sensor detect abnormal vibrations, but it does not detect what causes those abnormal vibrations. Some of the most common causes are:

  • Corrosion
  • Improper Mounting Of  Components Inside The Combustion Chamber
  • Damages In The Wiring
  • Mechanical Damage
  • Short Circuit In The Wiring

And in some rare cases, a faulty sensor could display a false alarm.  Nonetheless, wiring is a big issue and if you believe you’re suffering from wire damages, check out how to stop spark plug wires from arcing.

Steps to Take For a Knock Detection Code

The sensor is like a mini diagnostic tool and a handy one at that. It is connected to an ECM (Engine Control Module). So basically, as soon as the sensor notices abnormal knocking, it sends signals to ECM. To stop the engine from knocking or pinging, a signal is delivered to change the timing of the ignition or spark.

Depending on the signal sent to the ECM, a professional car mechanic could easily diagnose your problem. With certain tools, such a professional could easily pinpoint the faulty machinery inside your ignition chamber or elsewhere.

So after the inspection, instantly repair or replace the faulty components. Sometimes it could be caused by something silly such as a vital wire being disconnected or a socket stuck on spark plug.

Whatever it may be, the important thing to take away here is to instantly take a step. As the knock sensor code is nothing to be taken lightly. The very health of your engine, in the long run, depends on how smoothly it functions internally. This sensor ensures just that.

Symptoms Of A Faulty Knock Detector

So far we have discussed how important a knock detector is. With this sensor and some help from a car technician, we can easily diagnose many issues within the engine.  But what if our knock sensor’s faulty?

Well luckily, the sensor exhibits certain symptoms by which we can be informed.

More Fuel Consumption Than Usual

For a ride to school, we do have a clear idea of how much we pay for our fuels daily. If you notice that you are paying alarmingly more than usual for fuel, there’s a problem.

This sensor improves fuel consumption greatly. That is precisely why it is easy to spot a difference in terms of fuel consumption if we are aware.

Less Acceleration

If your car is accelerating slower than usual, you might wanna take a look at your knock sensor. As discussed above, a faulty sensor could deteriorate fuel consumption efficiency. And that normally leads to less acceleration over time. Which is kinda hard to spot and that brings us to the next point.

Lack of Power To The Engine

Lack of velocity is easy to spot. If you are having problems reaching high velocity, it means your engine lacks power. As we know, a faulty sensor reduces efficiency. And hence, reduces your engine’s performance.


So, can bad spark plugs cause a knock sensor code? As already mentioned, yes! Bad plugs can be a reason for it.

It is daunting to invest in the hobby of cars and vehicles. Especially when maintaining them can be so complicated. But trust me, with a bit of care and passion it isn’t soo intimidating. Learning all the in-and-out of your vehicle can take a bit time-consuming but is definitely worth it!

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