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Old 08-14-2010, 11:50 PM   #1
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Default Knock Retard

I finally bought a scangauge this week, and I am extremely happy with it.

What I am not happy with is my knock retard. I'll try to make this as simple as possible...

1. I get large bursts of KR (up to 83 at one point) that quickly fall back down to normal.
2. When just cruising I have 0 KR.
3. The bursts happen during moderate acceleration, with the throttle (more than) >10% open.
4. This happens in all gears, and only when the engine is warmed up (as far as I can tell).
5. I tried heavy acceleration (throttle >20% open) from ~5mph to 60mph, and got no KR until the car reached 4th gear, and then it went away once I let off the throttle.

I don't know much about KR, so could anyone help me understand it better? I have searched the forums and read this, but it doesn't really tell much about how to prevent/ reduce KR.
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Old 08-15-2010, 12:13 AM   #2
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Keep in mind that the knock sensor can pick up other vibrations or noises in the engine bay and register them as KR (false knock). I would verify that this isn't the case before assuming that your engine has asinine amounts of KR.
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Old 08-15-2010, 12:25 AM   #3
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Quote:
Originally Posted by xtremerevolution View Post
Keep in mind that the knock sensor can pick up other vibrations or noises in the engine bay and register them as KR (false knock). I would verify that this isn't the case before assuming that your engine has asinine amounts of KR.
Yea, I'm going to have a look around the engine bay tomorrow to see what I can find. The numbers seem way too high to be real.
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Old 08-15-2010, 01:37 AM   #4
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I wouldn't call that high
back in the days on clubgp and gpona some guys were scanning 6 to 7* of KR on a totally stock car
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Old 08-15-2010, 08:43 AM   #5
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Check for things like your exhaust touching something. That can give bad false KR
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Old 08-16-2010, 09:14 AM   #6
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When you hit 83, that sounds like you are watching the knock sensor noise channel. We shouldn't be able to get over 15 degrees of KR IIRC. Noise is always constant on the noise channel, but the actual KR is what we should be monitoring.
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