Diagnosing Knock Retard
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From: Cheyenne, Wy
Diagnosing Knock Retard Is there any way to diagnose knock retard to determine if it is false knock or detonation? I know I am pulling 12* of knock at idle and 3* to 5* knock at WOT.
Knock sensor and Knock module are both brand new.
It was not pulling any knock when we first loaded the tune but now it is. I need it to stop. I dont have any way to tug on the exhaust at the moment to make sure it isnt hitting because I can't really get under the car, so is there anything I can do to eliminate OR CONFIRM that this is detonation so I can move to the next step? This is the first time I have ever seen knock on my car so I am a little lost on how to make it stop...
Knock sensor and Knock module are both brand new.
It was not pulling any knock when we first loaded the tune but now it is. I need it to stop. I dont have any way to tug on the exhaust at the moment to make sure it isnt hitting because I can't really get under the car, so is there anything I can do to eliminate OR CONFIRM that this is detonation so I can move to the next step? This is the first time I have ever seen knock on my car so I am a little lost on how to make it stop...
I just dealt with this today. Run some high octane in it. That will determine if its false or not. I ran 105 octane through mine today just to make sure. Mines pulling up to 15* of timing at wot if i let it. Right now the max retard tables are set to 4*, so thats all it will pull.
The higher octane wont detonate, so if its false knock, the knock will still be there with the high octange.
The other thing i did to make sure it wasnt real knock was command 25* timing at all times. ( i have hptuners and can do this via the vcm controls on the scanner, 24x swap up in here
) Go for a rip with the timing set to only go to 25*max . Still pulling the same amount of timing in the same places, so i know that its not because of too much timing.
EDIT: Roller rocker noise will set it off also. Maybe go over that to make sure nothing loosened up
The higher octane wont detonate, so if its false knock, the knock will still be there with the high octange.
The other thing i did to make sure it wasnt real knock was command 25* timing at all times. ( i have hptuners and can do this via the vcm controls on the scanner, 24x swap up in here
) Go for a rip with the timing set to only go to 25*max . Still pulling the same amount of timing in the same places, so i know that its not because of too much timing.EDIT: Roller rocker noise will set it off also. Maybe go over that to make sure nothing loosened up
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From: Cheyenne, Wy
Ok, I got bck out there and fired it up with the datalogger on again. BEFORE this, at idle it was seeing 12* of Knock Retard. Just now, the Knock Retard ranged from 7 to 1 at idle...I have changed nothing.
Could ANY of this be related to a bad Coolant Temp Sensor? (The one in the WP, not the one for the gauge.) Just curious
Could ANY of this be related to a bad Coolant Temp Sensor? (The one in the WP, not the one for the gauge.) Just curious
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From: Cheyenne, Wy
I just dealt with this today. Run some high octane in it. That will determine if its false or not. I ran 105 octane through mine today just to make sure. Mines pulling up to 15* of timing at wot if i let it. Right now the max retard tables are set to 4*, so thats all it will pull.
The higher octane wont detonate, so if its false knock, the knock will still be there with the high octange.
The other thing i did to make sure it wasnt real knock was command 25* timing at all times. ( i have hptuners and can do this via the vcm controls on the scanner, 24x swap up in here ) Go for a rip with the timing set to only go to 25*max . Still pulling the same amount of timing in the same places, so i know that its not because of too much timing.
EDIT: Roller rocker noise will set it off also. Maybe go over that to make sure nothing loosened up
The higher octane wont detonate, so if its false knock, the knock will still be there with the high octange.
The other thing i did to make sure it wasnt real knock was command 25* timing at all times. ( i have hptuners and can do this via the vcm controls on the scanner, 24x swap up in here
) Go for a rip with the timing set to only go to 25*max . Still pulling the same amount of timing in the same places, so i know that its not because of too much timing.EDIT: Roller rocker noise will set it off also. Maybe go over that to make sure nothing loosened up
Ive read on some diy tuning websites that too much timing will cause it to ping/knock.
The high octane fuel will rule out fuel being the issue causing detonation. If you run high octane fuel in it and get no change in the knock then its a pretty good indicator its false knock.
Last edited by 97lt1camaro; Aug 13, 2012 at 01:28 AM.
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From: Cheyenne, Wy
If that was the case though, wouldn't have shown knock when I was tuning and datalogging it? Because I did some street driving and some WOT pulls on the current tune immediately after I loaded it and nothing...
Mine is only showing up at wot , high rpm and around .7 / .8 g/cyl area. I have nothing under 3000rpm.
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I have it EVERYWHERE, and it is the worst at idle...The ONLT time I am at 0 knock is when I accelerate then let off the gas...during decel it shows 0 knock...that is it
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From: Cheyenne, Wy
Ok, so I pulled off the driver side valve cover and checked the rockers...all looks good there. Nothing was loose or off. i didnt do the pass side because I really dont wanna take my alternator off tonight lol. I pulled out the #1 Spark Plug and looked at it...White Diode and white Tip with a small amount of light brown (almost copper) in there. No oil. Tells me it is running lean which I knew. Nothing looks overly out of the ordinary though. I will pull the pass valve cover off tomorrow and see what it looks like, an I am going to double check all of my exhaust to make sure nothing is hitting anywhere. If that doesnt fix the problem, it will be something in the tune and I will get my tuner to start tweeking it.
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From: POULSBO WA.
Usually when i see that much retard at idle its the km in the block. Either not hooked up correctly or broken wire maybe. Check for the 5 volt signal to it. I am sure SHBOX has a test proceedure to check it out.
yes, he means the knock sensor is supposed to read 5 volts with key on. Here is the test via shbox http://shbox.com/1/4th_gen_tech2.html I've heard if you over torque the knock sensor it could damage the sensor too.
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From: Cheyenne, Wy
Cruising it would bounce around a lot...anywhere from 5* to 0.06*. I am seeing anywhere from 0 to 44* of advance......It is bouncing around A LOT. At 40 mph and 2000 rpm's kPa is right around 40-45 and I am seeing 41-42* Advance.
WOT it was between 3* and 5*, I am showing 32-36* Advance at WOT with a kPa bouncing from 79 to 84. With the engine off my kPa is at 85.2
My timing is all OVER the place and it shouldnt be should it??
Not yet, I am flat broke and don't get paid for a few more days...
I just dealt with this today. Run some high octane in it. That will determine if its false or not. I ran 105 octane through mine today just to make sure. Mines pulling up to 15* of timing at wot if i let it. Right now the max retard tables are set to 4*, so thats all it will pull.
The higher octane wont detonate, so if its false knock, the knock will still be there with the high octange.
The other thing i did to make sure it wasnt real knock was command 25* timing at all times. ( i have hptuners and can do this via the vcm controls on the scanner, 24x swap up in here ) Go for a rip with the timing set to only go to 25*max . Still pulling the same amount of timing in the same places, so i know that its not because of too much timing.
EDIT: Roller rocker noise will set it off also. Maybe go over that to make sure nothing loosened up
The higher octane wont detonate, so if its false knock, the knock will still be there with the high octange.
The other thing i did to make sure it wasnt real knock was command 25* timing at all times. ( i have hptuners and can do this via the vcm controls on the scanner, 24x swap up in here
) Go for a rip with the timing set to only go to 25*max . Still pulling the same amount of timing in the same places, so i know that its not because of too much timing.EDIT: Roller rocker noise will set it off also. Maybe go over that to make sure nothing loosened up
