stock advance?
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Originally Posted by LT1Falcon
no, if i understand you right, i want to mess with the opposite, i want to add timing to the fields that are currently not knocking, but i figure once i start runnin 92 octane, i should be able to add a degree or 2 even the trouble areas (im guessin from about 1000 rpms to 3000 since i launch at idle).
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From: Charleston, West Virginia
Originally Posted by LiENUS
Once your running 92 octane you want to keep your car from pulling timing, add timing 1 degree at a time till you get KR then back off .5 degrees at a time till KR goes away. With KR you might only be running .5 Degrees too much timing but itl'l pull 2-3 degrees of timing.
Originally Posted by LiENUS
If the knock sensor is dead the computer does not detect any knock and does not pull any timing.
Originally Posted by LiENUS
Pinging is different from knock. When I added 5 degrees of timing there was no knock retard AT ALL. I scanned it and there is no knock retard. I didn't even get knock retard till 6 degrees and even then it was only .3 degrees of knock retard and once again you don't hear pining because... the computer pulls timing BEFORE you hear the pinging.
No I flashed my cars pcm with magic fairy dust. I have no data logging capabilities at all
No I flashed my cars pcm with magic fairy dust. I have no data logging capabilities at all
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Originally Posted by infinitebird
Sorry but you are completely wrong there, if the knock sensor is dead the computer will not be able to get any reading from it. If that is the case it sets a code 43 (not sure of the code on obdII) and it calculates knock retard based on preset operating parameters, but basically you will get almost a constant retard that is very high. Please see Injuneer's posts on cz28 where this is explained in much more detail.
I'm aware that pinging is different than knock, and if you did add 5 degrees everywhere with no knock, good for you. All I'm saying is that just because that worked for you does no mean everyone else will be able to do that. From the LT1's I've worked on, it's clear to me that most with moderate to high mileage will not be able to do that without seeing knock. It might just be the case that you have an exceptionally strong running car.
Originally Posted by LiENUS
it only throws a knock sensor code if the data is outside the expected range or if there is some form of short.
Originally Posted by LiENUS
its possible for it to stop providing accurate data to the pcm without the pcm knowing it.
In the GM shop manual the test it says to perform to determine if the sensor is bad involves measuring the resistance from the sensor to ground. If the resistance is outside the expected range, then the sensor is bad. However if that is the case, the voltage the pcm sees from the sensor will also be outside the expected range because the voltage drop across the sensor circuit will be affected in a nonstandard way by the nonstandard resistance of the sensor.
I'll give you that I suppose its possible for the sensor to fail in some way that would still provide the expected voltage, but that would be an unlikely event IMO. In most cases, if the sensor is dead, i.e. not working, the pcm will know about it and set the knock sensor code.
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Originally Posted by infinitebird
Those two statements make no sense together. If the sensor stops "providing accurate data to the pcm" that's almost certainly going to be "outside the expected range" and will therefore set the code.
In the GM shop manual the test it says to perform to determine if the sensor is bad involves measuring the resistance from the sensor to ground. If the resistance is outside the expected range, then the sensor is bad. However if that is the case, the voltage the pcm sees from the sensor will also be outside the expected range because the voltage drop across the sensor circuit will be affected in a nonstandard way by the nonstandard resistance of the sensor.
I'll give you that I suppose its possible for the sensor to fail in some way that would still provide the expected voltage, but that would be an unlikely event IMO. In most cases, if the sensor is dead, i.e. not working, the pcm will know about it and set the knock sensor code.
In the GM shop manual the test it says to perform to determine if the sensor is bad involves measuring the resistance from the sensor to ground. If the resistance is outside the expected range, then the sensor is bad. However if that is the case, the voltage the pcm sees from the sensor will also be outside the expected range because the voltage drop across the sensor circuit will be affected in a nonstandard way by the nonstandard resistance of the sensor.
I'll give you that I suppose its possible for the sensor to fail in some way that would still provide the expected voltage, but that would be an unlikely event IMO. In most cases, if the sensor is dead, i.e. not working, the pcm will know about it and set the knock sensor code.
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Originally Posted by infinitebird
^ I'm not sure how that pertains to what I wrote.
Fyi, here are the values:
for obd1: the resistance should be 3300-4500 ohms
for obd2: should be 93k-107k ohms
Fyi, here are the values:
for obd1: the resistance should be 3300-4500 ohms
for obd2: should be 93k-107k ohms
