Hello people,

Don't know if this is the correct section for my topic.

I ran a diagnostic test on my Ford AUII using ForScan, came up with Knock Sensor fault.

I assume this knock sensor somehow balances the engine from rough running.

Would this be caused by having the vehicle run on 10% Ethanol or would something else be causing the problem?

I'll post a pic of the result later tonight or tomorrow.

I'm not a sparky.

Cheers, Peter

from what i understand .. it adjusts timing etc to 'minimise' rough running

G'day Mad 2

Thanks, you are correct.

I could not load the image as it was saved in another computer as via screen capture.

I have written down what the fault was / is:-

DTC Code : P0325
Mode: PCM
Explanation: Knock Sensor 1 Circuit (Bank 1)
Alternative Explanation: Knock Sensor 1 Circuit Malfunction (Bank 1)
Detailed Explanation: The knock sensor detects vibrations upon increase and decrease in engine rpm. The knock sensor generates a voltage based on this vibration. Should this voltage go outside a calibrated level a DTC will set.
Possible Causes:
Knock sensor circuit short to GND
Knock sensor circuit short to PWR
Knock sensor circuit open
Damaged knock sensor
Damaged PCM
Diagnostic Aides: A knock sensor voltage greater than 0.5V with the key ON and engine OFF indicates a hard fault


Question:
How does one check this?

Where is the PCM located on a Ford AUII and how to test it if it is damaged?

Cheers, Peter

more inclined to think problem with knock sensor ... hopefully someone with more experience on this will come along

Mad2
Hopefully that's all it is.

In the past I did take the knock sensor off the car, gave it a clean and refitted to the vehicle. Bit fiddly work , does not seem much to the sensor itself.

It's a mongrel when curly ones like this crop up.

Hello,

The Knock sensor is a Piezo Crystal. If you hit one it will produce a small voltage. Shock ( mechanical ) = voltage. The ECU sees this and adjusts the timing to suit. They are used in Gas lighters and Scales also. If it cant see a voltage in the range it expects, it will report a fault. The shock from pinging is what the ECU is looking for, and keeps it running just before it Pings. That is why when you put in high octane fuel your car will run better with no change to engine settings. ( by you ) My understanding of how it all works.

Hello 96ELGli,

Thanks for explaining what the knock sensor is and how it works.

I know the manufacturer (Ford) says to run 91% unleaded, I know the vehicle can run on 95% unleaded. I've on a few occasions have used 10% Ethanol mix at 95 Octane.

I was wondering if the knock is due to running the car on 10% Ethanol mix?

Would there be a need to install a new knock sensor or leave it alone?

Maybe I should stick to normal 91% unleaded or the normal 95% unleaded.

Thanks

Peter

Easiest way is to grab a spare form the wreckers and bolt it up. If you have had to "clean" it before then there is probably a issue with the sensor.

Hello SWC,

Thanks , will do that. the only reason I cleaned the current knock sensor as it was grimey, bit of grease and dust build up on it.

I've driven over 220,000klm in just over 3.5 years since I had it.