DTC P0325 – How To Change a Honda Accord Knock Sensor

DTC P0325 – How To Change a Honda Accord Knock Sensor


The knock sensor in your Honda Accord is responsible for informing your Honda ECU of knock, or engine detonation. Detonation occurs in an engine when there’s not enough fuel or there’s something wrong with your 2.2 liter or 2.3 liter Honda F series engine ignition system. Regardless of the problem that could be causing the lean condition, you will need to replace or repair your Honda Accord knock sensor to fix the OBDII DTC P0325.

P0325 is informing you that the OBDII system in your Honda Accord has detected a problem with your knock sensor. The specific language behind this check engine trouble code is Knock Sensor Circuit Malfunction. This can mean one of two things, either your knock sensor has failed, or there’s a problem with the wiring harness that leads to your knock sensor.


Today I’ll be showing you how to change a Honda Accord knock sensor in a 2000 Honda Accord EX with a 2.3 liter F series SOHC engine in it. The Honda Accord knock sensor part number is 30530-P5M-003. This one pin sensor can also carry a part number of 30530-P5M-013 or 30530-PM5-013, and can also be found under certain Acura part numbers as well as Isuzu.

Where is my Honda Accord Knock Sensor Located?


This knock sensor is located underneath the intake manifold on your 2.3 liter Honda Accord F23 engine. It’s mounted to the back of the block right above the rear water pipe, and in order to access this sensor more easily, we’ll be removing the driver side axle.


If you have hands small enough and arms long enough, you may be able to sneak a 24mm deep socket behind your engine. This will allow you to gently crack the knock sensor loose and spin free. If you are not able to do this however, you will need to remove your driver side axle.

Chances are if your OBDII DTC P0325 has been lit on your dashboard, your Malfunction Indicator Lamp (MIL) should flash. This check engine light means that more than likely, your Honda Accord knock sensor has come apart.

This knock sensor is exposed to the elements and because of it’s location, can cool off and heat up quickly. This rapid expansion and expose to heat often cracks the knock sensor in half. This is completely normal, although you will still need to remove the base in order to replace the knock sensor.


You will need to unplug the oil pressure sender ( the rubber boot shown to the right of the knock sensor ) and then unplug your knock sensor. If you are removing your axle to complete our how to change a Honda Accord knock sensor DIY Guide, raise the front of your vehicle and secure it safely.

Remove the front driver side wheel to gain access to the axle nut. Undo the axle nut and spin it off the end of your CV drive axle. Next, you will be removing the sway bar end links, these are 14mm nuts that must be loosened.


Put the 14mm nut back onto the sway bar end link to ensure you don’t lose the nut. Now with the sway bar disconnected, you’ve got to disconnect the other side ( passenger side ) so that you can swing the entire lower control arm and axle out of the way. Next up on our how to change a Honda Accord knock sensor guide is disconnecting the outer tie rod.

Pull out the circlip from the castle nut on your outer tie rod, and then leave it disconnected from your hub assembly.


If your Honda Accord outer tie rod is damaged, or you need to replace it, check out our How To Service your Honda Accord tie rod DIY guide here.

The last part of removing your driver side axle is to remove the suspension fork that your shock absorber sits in. Disconnect this lower fork or pickle by undoing the 17mm bolt and nut that goes through the bottom of the fork and through your lower control arms.

The next bolt you’ll be disconnecting is the 14mm bolt that runs through the back of the suspension fork. This bolt holds the front shock in place, and once you’ve disconnected this 14mm bolt, slide off your suspension fork.


At this stage in our how to change a Honda Accord knock sensor article, you’re about ready to remove the driver side axle. Before doing this however, you will want to drain your transmission or at least have a pan ready for the transmission to drain into.

Remove the driver side axle, which will give you the room needed to service and change your Honda Accord knock sensor.


Now’s a good time to check your jackstands and make sure that your Honda Accord is safely and securely raised. Now you can crawl under your Honda Accord and look up into the engine bay to locate your Honda Accord rear water pipe and the knock sensor.


This knock sensor can be removed using a 24mm socket, and it must be deep unless of course your Honda Accord knock sensor is already broken.

Replace your knock sensor by simply screwing in your new unit and tighten to specification. Do not use any kind of anti seize or thread locker on this sensor, and do not use teflon tape to insulate the sensor. In order to clear your P0325 trouble code, you will need a scan tool to erase the stored DTC in your Honda Accord ECU.

This completes our how to change a Honda Accord knock sensor DIY article, if you have any questions regarding this How To or our DIY on fixing the P0325 trouble code, leave them for us below!


  1. I have changed my knock sencor code P0325 on my 2005 kia rio. After about 1000 miles, the code came back again. The same code as previously on bank one. Do you know what should I do to fix it? Or is it possible that the knock sensor got broken somehow? Or what would be the problem that could cause the check engine light come up?

    • Hi Paul! Thanks for commenting!

      Unfortunately, this replacement guide is for a Honda Accord, although your Rio won’t be much different. If you’ve already replaced your knock sensor with a new one, I would suggest trying to run your wiring back, or to find the knock sensor pin on your Kia Rio ECU and test the continuity.

      Thanks for commenting and let us know how it turns out!

  2. Hi,
    I have a 1999 Honda Accord 4cylinder VTEC. I received the car from my brother law and he basically said if you can figure it why the CEL comes on and you fix it it is yours.
    The code reader goes back and forth between two codes: P3025 and P1295

    Let’s address P1295:VTEC System Malfunction
    I checked engine oil pressure and it was fine according to specs.
    Replaced VTec solenoid
    Used a wire (touched positive terminal on battery) and touched the VTEC connector on solenoid to confirmed a click sound, I was told its a trick to confirm voltage to solenoid.
    Lastly, I replaced the oil pressure sensor to cancel out that it had gone bad.
    checked oils, replaced oil filter.

    I proceeded to clear the CEL with my reader and then…it comes back with a P0325

    P0325: problem with your knock sensor
    I replaced the knock sensor… (WTF)…I cleared CEL…and it comes back…

    Don’t know much about cars..just researching and asking alot… I haven’t quite checked the cable to the knock sensor because it is covered in a bunch of black protective tape…

    Will I need to cut open that black protective covering to access the cable and ensure that there is proper connection? Is it possible the cable is fried?…I am lost ast what to check next…

    • Hi Carlos, thanks for commenting.

      okay so your Accord has a few check engine codes. As for troubleshooting VTEC, that’s fairly straightforward. Here’s a guide on fixing any VTEC issues you have.


      It sounds like you’ve gotten a lot of VTEC troubleshooting done already, did you check to see if voltage was coming FROM the ECU to the solenoid?

      If your have replaced your knock sensor, and the code returns, check the wiring from your ECU to your sensor itself. This should give you a clear cut idea of what’s wrong.

      Thanks for commenting! Let us know how it turns out!

  3. I greatly appreciate the info on how to remove the knock sensor. But instead of removing the drivers side axle. I simply used a water heater Element Wrench. It fit perfectly around the knock sensor. And didn’t need a lot of room to maneuver around.