Difficulty Level

Tools/Supplies Needed:

• multimeter
• 12mm 3/8" driver socket
• 3/8" drive 3" and 6" extension
• 3/8" ratchet
• torque wrench

Procedure:

• first check for any breaks or corroded wiring/plug connections
• you can do a continuity test to determine if there is a fault wire within the circuit
• check for a clean ground connection between the sensor on the engine block
• check for any cracks in the casing of the sensor which would make it susceptible to moisture
• disconnect the wire
• using an multimeter, set it to the voltage setting, testing the harness on the ecu/vehicle side
• ensure there is an approximate 5V reading when the key is in the on position
• removing the sensor, using a 12mm socket, along with a 3" and 6" extension, you can access the bolt easily
• using a multimeter in the ohm setting to testing the sensor
• it should have a reading of 400,000ohm (400k ohm) or more which will determine that the sensor is still good
• ensure that the sensor is install in the proper position which is 60 degrees in accordance with the rear of the engine
• if the sensor does fail at any of the tests above, then it will need to be replaced
• reinstall the bold and tighten it to 24nm or 17.4ft lbs
• reinstall the wiring harness ensuring it isn't rubbing on anything

Frequently Asked Questions (FAQ):

I currently have a check engine light showing P0327 on my Subaru. Does this mean my knock sensor is faulty?

No it does not. Inspect the wiring for any damage or corrosion. Then determine if you are receiving the correct amount of voltage at the electrical connector. Next ensure the sensor has a clean ground source to the engine.