Knock on deacceleration??wierd
#1
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Knock on deacceleration??wierd
can someone please tell me,on couple of runs every time i log knock count i seem to get up to 10 knocks every time i let of the throtle.my timing seems to be fine but its wierd that every time i let offthe throtle i get good few knocks logged.
Would the dumpvalve noise maybe affect the knock sensors?
BTW, my evoscan wont let me save the logs so i cant upload the but only view them.
any ideas there?
thanks
Would the dumpvalve noise maybe affect the knock sensors?
BTW, my evoscan wont let me save the logs so i cant upload the but only view them.
any ideas there?
thanks
#2
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Could be something/anything that is physically hitting the engine or undercarriage when you let off the throttle.
See if you can use map tracer and see exactly where its occuring, drop timing in those zones severely and see if it clears up or goes away, if it doesn't its knock, if it does its artificial noise coming through as knock.
Scorke
See if you can use map tracer and see exactly where its occuring, drop timing in those zones severely and see if it clears up or goes away, if it doesn't its knock, if it does its artificial noise coming through as knock.
Scorke
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This can also be caused by backpressure. The exact same thing was happening when I was experimenting with the stock cat-back. Try reducing the timing values at the load cells that you're hitting when you lift the throttle. If it's something physical causing noise, you'll still get the knock counts. If you reduce your timing values and the knock reduces/goes away, then you know it's actual knock.
#7
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yup lift off detonation, except 10 seems kinda high, I was only seing 1-2. You can change your open loop maps to help that knock out without having to reduce timing. But as the guys mentioned, that much knock sounds like something is phycically banging around.
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