How to replace the knock sensor on Mazda 6?

In four-cylinder models, the knock sensor is on the front of the block, behind the bunds of the intake manifold. Starting with taking out the cable on the negative battery terminal and then take out the intake manifold. The second step includes disconnecting the electrical connector connected to the knock sensor, retaining bolt, and knock sensor. Installation is the opposite of removing, in making sure that the retaining bolt is snug according to the required torque. To check the V6 3.0L models, the first step is to disconnect the negative battery terminal, lift the vehicle safely on jackstands, and take off the engine compartment under cover. Unfit the electrical connector of the knock sensor, remove the retaining bolt and remove the knock sensor and then repeat the steps of the operation by reversing the steps and fitting the bolt back again with the required torque. In 3.7L models, where there are two knock sensors in the valley between the cylinder heads, disconnect the electrical connections of the knock sensors and remove the retaining bolts that hold the sensors. The process of reinstallation is in reverse order and the retaining bolts are tightened to the required torque.

Genuine Mazda 6 Knock Sensor

Engine Knock Sensor

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6 Knock Sensors found

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Mazda 6 Knock Sensor Part Number: LF01-18-921
$43.75 MSRP: $58.35
You Save: $14.60 (26%)
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Product Specifications
- Other Name: Sensor, Knock
- Replaces: 1F20-18-921A, 1F20-18-921
- Warranty: This genuine part is guaranteed by Mazda's factory warranty.
Fits the following Vehicles:
- 2003-2013 Mazda 6 | i, Mazdaspeed, S | 4 Cyl 2.3 L GAS, 4 Cyl 2.5 L GAS, 6 Cyl 3.0 L GAS
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Mazda 6 Knock Sensor Part Number: PE01-18-921
$62.38 MSRP: $83.18
You Save: $20.80 (26%)
Ships in 1-2 Business Days
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Product Specifications
- Other Name: Sensor, Knock
- Warranty: This genuine part is guaranteed by Mazda's factory warranty.
Fits the following Vehicles:
- 2014-2017 Mazda 6 | Grand Touring, Sport, Touring | 4 Cyl 2.5 L GAS
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Mazda 6 Knock Sensor Part Number: P31E-18-921
$93.71 MSRP: $124.98
You Save: $31.27 (26%)
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Product Specifications
- Other Name: Sensor, Knock
- Replaces: P32E-18-921
- Warranty: This genuine part is guaranteed by Mazda's factory warranty.
Fits the following Vehicles:
- 2018-2021 Mazda 6 | Carbon Edition, Grand Touring, Grand Touring Reserve, Signature, Sport, Touring | 4 Cyl 2.5 L GAS
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Mazda 6 Knock Sensor Part Number: L807-18-921
$114.39 MSRP: $152.54
You Save: $38.15 (26%)
Ships in 1-2 Business Days
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Product Specifications
- Other Name: Sensor, Knock
- Warranty: This genuine part is guaranteed by Mazda's factory warranty.
Fits the following Vehicles:
- 2006-2007 Mazda 6 | i, Mazdaspeed, S | 4 Cyl 2.3 L GAS, 6 Cyl 3.0 L GAS
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Mazda 6 Knock Sensor Part Number: AJ57-18-921A
Product Specifications
- Other Name: Sensor, Knock
- Warranty: This genuine part is guaranteed by Mazda's factory warranty.
Fits the following Vehicles:
- 2003-2008 Mazda 6 | i, Mazdaspeed, S | 4 Cyl 2.3 L GAS, 6 Cyl 3.0 L GAS
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Mazda 6 Knock Sensor Part Number: CY01-18-921
Product Specifications
- Other Name: Sensor, Knock
- Warranty: This genuine part is guaranteed by Mazda's factory warranty.
Fits the following Vehicles:
- 2009-2013 Mazda 6 | S | 6 Cyl 3.7 L GAS

Mazda 6 Knock Sensor

The Mazda 6 Knock Sensor is an engine protection device that detects when there is some form of harmful combustion knock and sends a signal to the powertrain control module to adjust the ignition timing to prevent damage to the engine. This piezoelectric device, mounted on the engine block, detects the spike of vibration that occurs with premature fuel detonation, converts this motion into an electrical signal, and commands the PCM to delay spark timing slightly until normal combustion resumes and to gradually increase the delay time again until power returns to normal. Since knock can be triggered by low octane fuel, high temperatures, or thin air at higher altitude, the sensor allows the vehicle to safely operate in a wide range of conditions while safely hovering at the optimal knock limit of efficiency and performance. In older Mazda models a single Knock Sensor was responsible for maintaining the overall ignition map; however, in Mazda 6 models later on the crystal element is coupled with smarter electronics for engine fine tuning and, in case the engine is turbocharged, may even adjust boost pressure to provide extra protection. This development helps Mazda engines to keep running, prevent the occurrence of piston or bearing damage, and give the engines easy drivability while consuming non premium fuel. With its quick feedback response, the third and last Knock Sensor in this list highlights why the said small element is a must in every modern gasoline powerplant in the brand.

Looking for Knock Sensor with proven quality? Choose OEM Knock Sensor. Mazda designs and builds them to strict factory specs. Every piece goes through rigorous quality checks. You'll get parts that fit right and work like new. Shop our huge inventory of OEM Mazda 6 parts. Enjoy the highly competitive prices online. Our site is your one-stop shop. Each genuine 6 part includes a manufacturer's warranty. Buy with confidence. Our return policy is simple and hassle-free. In a rush? Choose expedited delivery at checkout. You'll love the streamlined experience from search to checkout to receiving your order.

Mazda 6 Knock Sensor Parts and Q&A

Knock Sensor
L807-18-921
Q: How to replace the knock sensor on Mazda 6?
A:
In four-cylinder models, the knock sensor is on the front of the block, behind the bunds of the intake manifold. Starting with taking out the cable on the negative battery terminal and then take out the intake manifold. The second step includes disconnecting the electrical connector connected to the knock sensor, retaining bolt, and knock sensor. Installation is the opposite of removing, in making sure that the retaining bolt is snug according to the required torque. To check the V6 3.0L models, the first step is to disconnect the negative battery terminal, lift the vehicle safely on jackstands, and take off the engine compartment under cover. Unfit the electrical connector of the knock sensor, remove the retaining bolt and remove the knock sensor and then repeat the steps of the operation by reversing the steps and fitting the bolt back again with the required torque. In 3.7L models, where there are two knock sensors in the valley between the cylinder heads, disconnect the electrical connections of the knock sensors and remove the retaining bolts that hold the sensors. The process of reinstallation is in reverse order and the retaining bolts are tightened to the required torque.