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Discussion Starter · #1 ·
Hi,

Not sure if i have a fault or not. My remote box displays a p0325 fault code, but my £250 snap on code reader doesnt display the fault.

My ecu is locked so will this affect the code reader part of my remote box or is there a reason it doesnt display on anything else?

I dont get any lights on the dash regarding this fault.

Anyone in central Scotland got access to clip?

Thanks
Steven.
 

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Discussion Starter · #2 ·
Going to get a lambda sensor from renault today, if they have one in stock.

If his is the fault should the fault on the remote box clear?
 

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Don't bother with a Renault Lambda sensor... just get a Bosch / NTK equivalent, same part half the price.
 

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Knock sensor fault and you are buying a lambda??? I'm lost here.

Is the knock sensors wiring intact? Been working around it recently/
 

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Discussion Starter · #6 ·
I thought i would have a knock fault because i had a fuel related issue due to either lambda or fuel pump?

Where is the knock sensor located?
 

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No, you'd get a misfire fault if that were the case. It depends on the fault definition which you won't get without clip but its 99.9% a problem with the sensor or its wiring.
 

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Discussion Starter · #8 ·
Cheers mate, i was looking at a fuel fault causing knock.

Where is the sensor located?

Is it 3 pin plug? (12 volt feed, earth and signal wire?)
 

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Knock sensor is on the front of the engine, Near the oil filter..

I've not really heard of the sensors failing, as Ben said have you checked the wiring / connection?
 

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I've had a knock sensor fail. Limits power and goes into a "safe" but silly over fuelling default mode. No dash lights so you'd potentially never know if you weren't switched on.
I've also heard of people damaging it when changing the oil filter as it's right next to it.
 

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Discussion Starter · #13 ·
My cars running at 19mpg and that's me driving under 3k rpm with no harsh acceleration.

So the knock sensor works like a microphone. So 2 wires....I guess its a 12volt reference feed and the sensor works like avariable resistor putting a biased voltage back to the ecu which in turn advances and retards the spark??

Ill check the wiring when replacing the sensor, just incase its chaffed/ open circuit somewhere.
 

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Nope, it'll work like a microphone producing an AC waveform which can be interpreted into sound. Its tuned to the specific frequencies or vibration that knock/det creates, ECU monitors the level of these vibrations and interacts if necessary.

Will also monitor resistance to ensure the sensor is connected and not obviously faulty.
 

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Discussion Starter · #15 ·
So without proper diagnostic equipment (clip) there is no way to check if the sensor is working correctly?
Sorry mate not that clued up on knock sensors as I never deal with them.
So the ac waveform signal will be interpereted to the ecu as pwm (pulse witdth modulation) voltage and if the rythm/ waveform is wrong it interacts??
Do you know what pins and plug the wiring goes to at the ecu?
 

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Tbh i dont have a clue whats going on but just by chance i found this image that BMH.01 had posted up on another thread regarding the knock sensor being damaged by an oil change.

Its the brown plug
 

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wow be very very carefull. I blow my motor after a knock senzor error. How i sorted this out? I unplugged the wire from the sensor and putted back in. After that I erased my error. and took out the battery to reset the ecu. Please do no drive with the knock sensor error. Sorry for my english
 

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Discussion Starter · #19 ·
The car hasn't turned a wheel since I realised the fault was on the remote box!

I now have the knock sensor and will fit it tonight and check the wiring....hopefully its just the sensor.
 

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Discussion Starter · #20 ·
Replaced the knock sensor :) found the outer casing seperated from the internals.
pretty awkward to reach, so removed the throttle body, dump valve and silicone hose to gain access.
Had a quick look at the wiring and could only trace it so far without wiring diagrams.

Connected my remote box and for the first time since i noticed it the fault has now cleared. Driven the car 8 miles varying throttle etc and the only fault i have is my stupid smf code.
Mpg is now at 24.7 instead of 19 and the throttle response feels alot better.

Thanks for the help guys :)
 
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