Getting weird knock
08-08-2011, 01:55 AM
#1
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Getting weird knock Hp tuners is showing a block type of knock starts at 2* and steadily goes to 4*KR then back down. Now, i know that is the actual sensors are bad it will read 4*KR all around in most of the cells.
Im almost 90 % sure its false knock, Ive checked and ran just c16 and it still 'knocks'. Also note, i re-used my old knock sensors from my old motor, they didnt have many miles on them. Could it be the the wiring harness going to the sensors?? Any help. I know the wires of these may be jacked up because I have had fifty million different intakes on my setup. Thanks guys
Should i turn down the sensitivty of the sensors as well or is that just wasting time?
Im almost 90 % sure its false knock, Ive checked and ran just c16 and it still 'knocks'. Also note, i re-used my old knock sensors from my old motor, they didnt have many miles on them. Could it be the the wiring harness going to the sensors?? Any help. I know the wires of these may be jacked up because I have had fifty million different intakes on my setup. Thanks guys
Should i turn down the sensitivty of the sensors as well or is that just wasting time?
08-08-2011, 02:03 AM
#2
i actually just experienced this. got it on the dyno and boom knock.
i had a bad harness so i replaced it and took it back to the dyno and it was the same story. however it wasnt all the time it would pick up knock worse on some passes then others. then it hit me. its hot as ****. the dyno room conditions were 109 and the air was thin as ***** and hot as hell. we let it cool off for the final couple passes and the final pass was even a spray pass and zero knock. if you have full faith in your tuner like i did because my tuner is a complete badass id chalk it up to being this wicked southern heat, higher than normal water temps, and false knock.
i had a bad harness so i replaced it and took it back to the dyno and it was the same story. however it wasnt all the time it would pick up knock worse on some passes then others. then it hit me. its hot as ****. the dyno room conditions were 109 and the air was thin as ***** and hot as hell. we let it cool off for the final couple passes and the final pass was even a spray pass and zero knock. if you have full faith in your tuner like i did because my tuner is a complete badass id chalk it up to being this wicked southern heat, higher than normal water temps, and false knock.
08-08-2011, 01:41 PM
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so its heat causing false knock? doesnt make sense, i could see it actually pulling timing because of the IATs but i dont knw if it will knock because of actual heat?
08-09-2011, 01:02 AM
#4
well do you know what your iat's were? my car is sd and it was 109 in the dyno room and the afr was good and the timing was at 20 degrees and it was still picking up the wierd some worse than others knock you described. however we let it cool off by going to lunch and leavin a fan on it and we made a pass when we got back and boom zero knock. engine temps effect it alot too think about how those heads feel gettin ran to the max with being heat soaked on top off higher than normal water temps. it may not be false knock it could be actual detonation due to heat or whatever
08-09-2011, 02:33 PM
#6
Just to clarify, knock caused by high air temperatures is not false knock, it is very real.
High temp air does cause real knock, thats why FI people use intercoolers, CO2 sprayers and water/meth injection, just to lower intake air temperatures.
Be very careful with knock, don't just desensitize your knock sensors because you may damage the engine.
If it goes away with cooler temperatures, beware. It is real knock and should be dealt with first.
High temp air does cause real knock, thats why FI people use intercoolers, CO2 sprayers and water/meth injection, just to lower intake air temperatures.
Be very careful with knock, don't just desensitize your knock sensors because you may damage the engine.
If it goes away with cooler temperatures, beware. It is real knock and should be dealt with first.
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08-09-2011, 03:57 PM
#8
If knock doesn't go away with this, then it is false knock for sure
08-10-2011, 12:42 AM
#10
my afr was good and the fuel was good. i didnt think to ask about iat's but i figure the thin *** air and hot *** temps had to be it because he could make the knock go away with taking away timing thats what made me think it was the temps because the timing being conservative afr being good and the gas being good didnt make sense it would keep knocking
