CEL P0328 - Knock Sensor (high input bank 1)


Team PRO5
02 Mazda 323 Astina SP20 (P5)
Hey guys,

Over the past few mornings I have had CEL P0328 appear on the ScanGauge - Knock Sensor (high input bank 1)

Possible causes
- Knock sensor circuit short to GND.
- Knock sensor circuit short to PWR.
- Knock sensor circuit open.
- Damaged knock sensor.
- Powertrain Control Module (PCM

Possible solution
- Repair or resecure harness or connector
- Replaced knock sensor

When is the code detected?
- An excessively high voltage from the sensor is sent to Powertrain Control Module (PCM) or Electronic Control Module (ECM)

P0328 Description
The knock sensor is attached to the cylinder block. It senses engine knocking using a piezoelectric element. A knocking vibration from the cylinder block is sensed as vibrational pressure. This pressure is converted into a voltage signal and sent to the Powertrain Control Module (PCM) or Engine Control Module (ECM).

I have checked the connector this morning and seems to be fine (from what I could feel - the knock sensor is above the oil filter so a total PITA to get to). I have only been running 98 octane fuel for the past 6-8mths, so im not getting any pinging. Its only appearing on teh scangauge of a morning, with the current temps in ipswich at 7.30am around 5degrees the past couple weeks :eek: The car is warmed up for around 1-2mins before being driven, and im averaging around 500kms/tank, even with the colder weather..

So, in saying, the Knock Sensor talks to the ECM in which it retards or advances the timing, so could the colder weather be tricking the car and making the cel appear? On the weekend Im going to be going back to stock intake to see if this makes a difference.

Any other suggestions? I really dont want to fork out $180usd for a new one, and I would hate to know how much one would cost here in Aus! :eek:



___ 323F ___
When you say "go back to stock intake" did you mean intake manifold or air intake? Not sure how air intake or manifold would make this happen. My buddy's 04 6 knock sensor used to give him fits and was not easy to get to on the KL. May just be time for new sensor but I understand the being sure first due to the price of the piece. I would have to bust out multimeter on harness side and sensor side before dropping coin. Let us know how it plays out..........
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Team PRO5
02 Mazda 323 Astina SP20 (P5)
I meant air intake - Im currently running a AutoExe SRI and was going to go back to stock, even the paper filter! :(

My train of thought is that the colder temps now we're going into Winter will see more fuel being thrown into the mix, timing being advanced to a point where its throwing the cel. Now the odd thing is that we experienced out coldest morning today at 3
degree's, and I didnt get a CEL (confused)

I have been able to source another knock sensor from a mate, so will try it out over the weekend..