Knock Sensor
88MKIII
03-04-2005, 04:51 PM
I wen't to get my check engine light checked and accordint to it is the knock sensor, and the air intake temprerature sensor. Any one knows how much does the knock sensro affect performance? What is the function of the knock, and air intake temperature sensor?
projectsupramk3
03-04-2005, 05:14 PM
So you already know about code checking and the TSRM, that's a very good start.
http://www.cygnusx1.net/supra/techtips.html
The KS code is probably caused by the wiring, it's old and crusty and is most likely introducing alot of noise into the sensors. Just follow the rewire directions and take your time, you shouldn't have any problems.
http://www.supras.com/04/resources/index.php?q=knock
Code 24 could be a bad AFM, or just some loose wires/connection. Hard to say either way but there is a resitance check described in the TSRM for it to make sure the sensor is ok.
http://www.cygnusx1.net/supra/techtips.html
The KS code is probably caused by the wiring, it's old and crusty and is most likely introducing alot of noise into the sensors. Just follow the rewire directions and take your time, you shouldn't have any problems.
http://www.supras.com/04/resources/index.php?q=knock
Code 24 could be a bad AFM, or just some loose wires/connection. Hard to say either way but there is a resitance check described in the TSRM for it to make sure the sensor is ok.
88MKIII
03-04-2005, 07:57 PM
thanks for the info, i'm not familiar with wiring and solding so i i'll just buy a new sensor. thanks. By any chance do yo know how can the sensor affect engine preformance?
Derby
03-05-2005, 03:05 PM
The knock sensor senses when the mixture is igniting too early or too fast.
When the mixture is burning to fast it could be that the intake air is to hot. (that is after the IC). The compression increases temp also. so temp and pressure make the mixture explosive. A spark should start the burning of the mixture in a controlled way. slowly and controlled.
But with rising temp, the mixture somewhere else in the cil could start buring also without the touch of the flamefront. that selfburning thingy burns faster then the rest. and will be more of a explosion then a fire.
This explosion gives a vibriation, other then the other vibrations in the engine (valves hitting the valve seats). the sensor is triggered by a special freqency. the freq of the explosion. This signal is given to the ecu and this unit desides if there is any action needed. If knock is detected, the ignition timing is retarded.
And ignition timing is a very good tool to change torque.
So a broken knock sensor and/or Air temp sensor do affect power.
Derby
When the mixture is burning to fast it could be that the intake air is to hot. (that is after the IC). The compression increases temp also. so temp and pressure make the mixture explosive. A spark should start the burning of the mixture in a controlled way. slowly and controlled.
But with rising temp, the mixture somewhere else in the cil could start buring also without the touch of the flamefront. that selfburning thingy burns faster then the rest. and will be more of a explosion then a fire.
This explosion gives a vibriation, other then the other vibrations in the engine (valves hitting the valve seats). the sensor is triggered by a special freqency. the freq of the explosion. This signal is given to the ecu and this unit desides if there is any action needed. If knock is detected, the ignition timing is retarded.
And ignition timing is a very good tool to change torque.
So a broken knock sensor and/or Air temp sensor do affect power.
Derby
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