December 26, 2023

Engine Knock in a 2009-2010 Acura TSX: Let’s Fix It Together

Acura TSX PCM ping engine knock knocking Knocking, unfortunately it’s all too common to develop engine knock (due to the sensor) in the Acura TSX, specifically the 2009-2010 models. It’s distressing to hear that unusual ping from half throttle to full throttle. Luckily there’s a straightforward solution in the form of a powertrain control module (PCM) software update.

Check for recalls.

What is it?

This pinging sound is most noticeable when accelerating from half throttle to full throttle.  Engine pinging, occurs when the air-fuel mixture in the engine’s cylinders is ignited prematurely. This premature ignition causes a knocking noise. Don’t ignore this, there’s a high potential for engine damage.

Diagnose

  1. Listen: Listen for a pinging or knocking sound when accelerating.
  2. Codes: Use an OBD-II scanner to check codes like P0325.
  3. Inspect the Sensor: Located on the engine block, the sensor detects engine knock and sends this information to the PCM.  The sensor informs the Engine Control Unit (ECU) of these occurrences, and the ECU adjusts the timing and fuel mixture to prevent engine damage.
    • The sensor looks like a small, round device, usually made of plastic or metal. It has an electrical connector on one end and is bolted to the engine block on the other. It’s not very, about the size of a coin (though thicker).
      1. Look for for any obvious damage, cracks, corrosion, or wiring and connector for damage.
      2. Disconnect the Sensor
      3. Set your multimeter to the resistance (ohms) setting.
      4. Measure the resistance across the sensor’s terminals.
      5. Check the service manual, typically in the range of several hundred kilo-ohms to over a megaohm
      6. Reconnect the sensor.
      7. Back-probe the sensor connector and measure the voltage with the engine running.
      8. You should see a baseline voltage (refer to the manual for specific values), and it should fluctuate as the engine is revved (indicating the sensor is detecting vibrations).

OBD Codes

  • P0330: Knock Sensor 2 Circuit Malfunction
  • P0328: Knock Sensor Circuit High Input
  • P0332: Knock Sensor 2 Circuit Low Input

See all the OBD codes here.

PCM Software Update for Your Acura TSX

Acura provides an update for the sensor and PCM software, which resolves the pinging.  Check with a professional mechanic or your Acura dealer.

Final Thoughts

I hope you feel more comfortable about what to do. Remember, if you’re ever in doubt, professional advice is just a dealership away!