Code P0325 Knock Sensor 2004 Honda Civic

Check engine light came on with code po325 knock sensor; is this why the car is vibrating on idle?  already replaced front engine mount.

It is a possibility that the code P0325 is causing the vibration at idle. Depending on the signal the engines computer receives from the knock sensor it will advance or retard the ignition timing.

Time Saver Tip

If you decide you need to replace the knock sensor check out the video below to avoid having to remove the intake manifold as instructed in the repair manual.

Honda Code P0325

Code P0325 – Knock Sensor 1 Circuit Bank 1 or Single Sensor

DTC P0325 Knock Sensor Circuit Malfunction

1. Reset the ECM/PCM
2. Start the engine. Hold the engine at 3,000 rpm without load(in Park or neutral) until the radiator fan comes on, then let it idle.
3. Hold the engine at 3,000-4,000 rpm for at least 10 seconds.
   Is DTC P0325 Indicated?
   YES – Go to step 4.
   No – Intermittent failure, system is OK at this time. Check for poor connections or loose terminals at the knock sensor and at the ECM/PCM.
4. Turn the ignition OFF.
5. Disconnect the knock sensor 3P connector.
6. Turn the ignition switch ON.
7. Measure the voltage between knock sensor 3P connector terminal No. 1 and body ground.
   Is there about 5V?
   YES – Go to step 12.
   No – Go to step 8.
8. Measure voltage between ECM/PCM connector terminal A9 and body ground.
   Is there about 5V?
   YES – Repair open in the wire between the ECM/PCM (A9) and knock sensor.
   No – Go to step 9.
9. Turn the ignition OFF.
10. Disconnect ECM/PCM connector A (31P) from the ECM/PCM.
11. Check for continuity between ECM/PCM connector terminal A9 and body ground.
    Is there continuity?
    YES – Repair short in the wire between the ECM/PCM (A9) and knock sensor.
    No – Update the ECM/PCM if it does not have the latest software, or substitute a known-good ECM/PCM, then recheck. If the symptom/indication goes away with a known-good ECM/PCM, replace the original ECM/PCM.
12. Substitute a known-good knock sensor and recheck.
    Is DTC P0325 indicated?
    YES – Update the ECM/PCM if it does not have the latest software, or substitute a known-good ECM/PCM, then recheck. If the symptom/indication goes away with a known-good ECM/PCM, replace the original ECM/PCM..
    No – Replace the original knock sensor.

How to replace the Knock Sensor without removing the Intake Manifold.

Purchase Knock Sensor

I looked this one up for a 2004 Honda Civic SI