i really need help..
- Thread starter Ghost 12
- Start date
philstarletgt
Member +
was it replaced with a genuine one? some after market ones are really shite and dnt last long
dac69er
Super Moderator
sounds like its not working. i had the same problem when the connector was broken. is the cable and connector definitely 100% all the way to the ecu?
if it is then it can only be the knock sensor. you will have to change it again. is the knock sensor brand new or second hand? is it from a starlet or another car?
if it is then it can only be the knock sensor. you will have to change it again. is the knock sensor brand new or second hand? is it from a starlet or another car?
dac69er
Super Moderator
really? surely it shouldnt matter as long as its tight? i cant see why it would affect it unless it was overtight and damaged it or too loose to cause vibration. i never torqued mine up and its fine.
weeJohn
Lifer
As you spark you probably might know this already, its a piezoelectric sensor, which when pressure is applied to (in this case, pressure waves through the block caused by detonation in the cylinders) causes the crystal inside to produce a current or voltage.
If its torqued up to much then there is a certain ammount of pressure already on the sensor base and there fore a certain ammount of current already being produced, and if its not tight enough then the opposite is the case.
If its torqued up to much then there is a certain ammount of pressure already on the sensor base and there fore a certain ammount of current already being produced, and if its not tight enough then the opposite is the case.
hello it is a second hand because the nwe one is rellay expensiv.
the cabel is ok.
or should i make a new cabel from the sensor to the ecu?
i dont think the engine is knocking because the engine is rebuild with new piston(low compression)
is it posibly that the ecu is broken?
thanks
the cabel is ok.
or should i make a new cabel from the sensor to the ecu?
i dont think the engine is knocking because the engine is rebuild with new piston(low compression)
is it posibly that the ecu is broken?
thanks
Last edited:
weeJohn
Lifer
No, as revs change then so would the frequency of the det. It detects lots of vibrations from the engine as it rotates, its only when you get a bigger pressure wave through the block caused by detonation that its enough to trigger an output from the sensor.
It possibly only looks at it for a moment in time after the spark is triggered on each cylinder to prevent false knock readings, but I dont know if thats true or not.
@Ghost, I would check the wiring back to the ECU is good and if its not I would try another sensor that you know is OK.
dac69er
Super Moderator
i know the frequency will change, but you said it is looking for a pressure. it isnt, it is looking for a frequency.
i would imagine it is setup to throw the engine warning light up when i sees a certain frequency at a certain amplitude. i wouldnt have thought it is particularly accurate, it is just for safety. the engineers probably know the most common frequency of the knock on this engine and use that.
that is essentially how you set up some of the other aftermarket knock sensors. you pick a frequency or a small frequency range and an amplitude and that creates your knock level.
dac69er
Super Moderator
the outside of the cable is a shield to try and stop any current from any other cables from causing spikes or incorrect readings. the inside cable is the signal cable which needs to be perfect condition with no bad connections due to the low voltage used.