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Why would the knock sensor trouble code keep coming on?


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2011-09-13 17:23:52
2011-09-13 17:23:52

depends on what kind of car it is. On most supercharged, turbocharged,and cars with high compression ratios the knock sensor code would come up because you didnt put high octane fuel in the car. the lower the octane rating of the fuel, the more unstable the fuel is under pressure, which means the fuel would ignite before the spark ignites it, causing the timing to be off and the Check Engine lite to come on

ANSWER from smokingallowed....

I just came from there. I can tell you I kept getting a P0325 code, which is Knock sensor circuit 1 fault. I have another knock sensor sitting around,so I swap them out. The code kept coming back. I KNOW they work because to test them,get your meter, clip the red(+) meter wire to the the plug-in side of the sensor and the black(-) meter wire to the caseing of the sensor if its the one wire type. If its 2 wire type connect the two meter wires to the two sensor prongs on its plug on the sensor. Then set the meter to the lowest AC setting.(Not DC) Knock sensors produce AC voltage. Then bang on the side of the sensor and watch the voltage spike..If it don't change the sensor is bad. But anyway, It's still doing the same even with different knock sensors. I'm starting to think bad gas,but there was no knock. So I removed the sensor again took a wire brush to the threads of the sensor AND the thread of the block where itscrews in. I learned that don't overtighten it.It should be torqued to Appx. 14 ft. lbs. I set mine at 10lbs. But first I wrapped it in a towel so it wont bang on anything and then drove the car with it being unscrewed from the block. The code STILL came back. So I double check the threads for cleanliness. Screwed the oridgenal sensor back into the block. I tested the plug that comes from the car for voltage.It was somthing low like 4 or 5 VDC in which it is supost to be. Then pluged it back in and THAT was the problem.NO MORE KNOCK SENSOR CODE P0325. In short words,MAKE SURE that the sensor has a good clean connection where it screws into the block...because that is the ground for the sensor and if its not makeing good contact with the block you will have a P0325 (Knock Sensor Circuit 1 Fault (or short) I also replaced the knock sensor plug on the 97 z24..... So remove the sensor,test it as outlined above,clean the sensor threads, and the threads on the block, twist the wire that you will be plugging into the sensor a few times So you can be sure the plug is pluged in very good. I have read that these are screwed into the water jacket,but the past 8 knock sensor I have removed from blown 2.4L DOHC engines NONE were screwed in the water jacket.

Dont get the above code mixed-up with the P0326 CODE. Which is Knock Sensor Circuit Performance. That will be the sensor is failing or has already failed, or the 4 or 5 volts is not reaching the knock sensor.

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Where would the knock sensor be located on a 2004 mazda 6?

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I have a 240 and with the knock sensor unplugged it will still start so I would have to say no.

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If just the knock sensor need to be replaced. I would say no more than $150.00

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Knock sensor codes on this vehicle are meaningless, the knock sensor does nothing unless the engine knocks. If you have this code there is more than likely a problem in one of the other emission-related devices, which often triggers this code first. My advice is to ignore it until another code pops up giving you more information about where to look. Do not replace the knock sensor, it will be expensive and will not stop the code from reappearing. Loading... >>

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No. It only senses engine vibration/knock.


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