How to Replace Knock Sensors On Chevrolet Silverado?

A knock sensor is a sensor device that can identify the high-frequency vibration in engine knwon as knocking and emits a wireless signal to the Engine Control Unit ECU. A bad knock sensor can be replace in a multi step process, that involve disconnecting batteries, removing engine manifold, unpluging and unscrewing sensor, replacing the sensor and finally reassembly the complete setup.

Knock sensors play a vital role in a vehicle’s engine functionality. It closely work with engine ECU to control the vehicle engine working. Knocking Sensor work to detects any kind of engine unwanted vibrations and send data to engine cintrol module ECU for controling ignition timing.

A bad knocking sensor cannot feed the ECU properly and thus can cause serious performance issue like low millage and reduce torque. Being a Chevy Silverado owner you can face this problem alot and if you don’t know how to replace the knock sensor Chevy Silverado, just follow us.

How the Knock Sensors operate

In an engine, its required to start the ignition as early as possible to get maximum fuel burning. Any delay or premature ignition will result in high frequency vibrations and sharp sound known as knocking.

Knocking sensor sense vibrations and send this data to ECU so that it can control the spark plug or fuel ignition timing. A bad knocking sensor cannot work with ECU to control ignition timing thus can cause serious engine performance issues. It can also cause lower fuel efficiency and reduce engine power.

Symptoms that say you have a Bad Knock Sensor

As you’ve known that a faulty knock sensor can cause engine performance issues. So its important to know bad knock sensor symptoms. Following are the Chevy Silverado bad knocking sensor symptom.

  • Check Engine Light
  • Loud noise or high fequency vibrations
  • Poor Fuel Millage
  • Reduce Torque

Check Engine Light

Like every vehicle every Chevy Silverado has a check engin light whose main function is to alert drive that there is something wrong with engine. With bad knock sensor there will be wrong information being send to ECU, forcing it to make bad decisions that results check engine light to be illuminated.

Loud Noises or High Frequencies

If you hear some thoroughly loud noises from the engine without any reason, then you might consider that you have a faulty knock sensor. A bad knock sensor will make ECU to make premature of delayed ignition result is loud knocking sounds from engine. This also make engine parts specially piston, connecting rod, and valves to vibrate.

Poor Engine Performance

With a bad knock sensor, there will a promenent poor engine performance interms of reduced power, reduced torque, and poor fuel millage. All these problems are due to ECU failing to ignite the fuel at the right time. Premature ignition or delayed ignition will result in imcomplete burning of fuel.

How to replace 2006 Chevy Silverado Knock Sensor

You might be wondering why we’ve chosen the 2006 Chevy Silverado here. Well, it’s because the Chevy Silverado 2006 was the most controversial Chevy Silverado model ever. There were problems with the emergency brake, bad paint, a faulty engine, and many other. 

So, it’s common to have a faulty knock sensor in your 2006 Chevy Silverado and we know that you need to replace knock sensor 2006 Silverado. Let’s see how you can do that.

Accessing the Intake Manifold

Following following steps to access the intake mainfold.

  • To start the process you have to disconnect the negative battery so you dont get electric shock.
  • The next thing do is to removing the engine intake hoses (has to be removed from both ends).
  • After that, start removing the throttle plug and cruise control plug from the body. 
  • Now, remove the throttle channel bracket from the manifold and push that throttle channel bracket along with the plugs.
  • Then, you have to remove the bolts that are holding the main engine on the vehicle’s driver’s side.
  • You have to unplug a total of three parts now, the MAP sensor, the EVAP solenoid, and the knock sensor’s sub harness.
  • Then, remove the throttle body as you’ve unplugged and unbolted all the necessary parts. Start removing the vent channels from the valve cover.

Following all these steps will lead you to an exposed intake manifold.

Removing the fuel lines

You can use a fuel line remover to easily remove fuel lines from the rails. The rail that has fuel lines are present on the rear side of manifold on the driver side of the vehicle. Use the same fuel line remover to remove the EVAP line that is located between engine and firewall.

Removing the injectors and the engine wire harness

First, you need to unplug all of the eight fuel injectors and the injector connectors. Once you’ve done that, disengage the vacuum line from the brake’s servo first and then from the vehicle engine wire harnedd.

Now finally remove the alternator from the engine wire harness and then you can finally replace the knock sensor.

Replacing the Knock Sensors

You need to loosen up all of the intake manifold bolts or screws in the reverse order of which they were initially screwed that is 10 to 1. Then, pull off the intake manifold. 

The knock sensors are situated under the black channels affixed with a wire gear. Pull out the plugs and loosen up the bolts of the knock sensors while using a 22mm cavernous socket.

Lodge the new knock sensors and torque the sensors to 15 ft-lbs. Then, apply RTV to the rubber channels to prevent water from plunging in.

Mount all of the removed parts

Now is the time to re-install all of the components you’ve taken out. Let’s start with clipping the new intake manifold coverings to the intake manifold. Remember to clean all of them.

Try to set the removed manifold back to the engine and torque the unbolted bolts in the correct order which was 1 to 10. Now, place the throttle body back to its original place and torque it.

Engage the knock sensor channels from the wire gear and plug all of the remaining sensors in. Re-engage the fuel lines and the EVAP line which you removed earlier with a fuel line remover. Finally, connect the negative battery console back to its place and you’re good to go.

Replace Knock Sensors On Chevrolet Silverado infographic


Look, we know that we’ve bored you until now, but bear with us a little more. Normally replacing a knock sensor from your Chevy Silverado would cost you around 250 US dollars to 300 US dollars if you go to a repair shop.

Whereas if you fix the knock sensors of your Chevy Silverado on your own, you can save that money, right? So, all the best to replace the knocks sensors if you are doing it for the first time.

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William Baldwin

This Is William Baldwin, The Founder & Managing Editor of this website. Me and my team share automotive tips, tricks, and news

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Talha Atta

Talha Atta, a Mechanical Engineer and experienced technical content writer and editor at with a passion for the automotive industry.