- KC on take off
05 October 2006, 08:38 AM
#1
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- KC on take off
I have 2002 WRX. It has recently started registering - negative knock correction on take off.
1. The - KC only occurs on clutch take up from stand still.
2. There is no - KC anywhere else in the rev band
I surmise there might be a loose object confusing the KC. What should I check?
1. The - KC only occurs on clutch take up from stand still.
2. There is no - KC anywhere else in the rev band
I surmise there might be a loose object confusing the KC. What should I check?
05 October 2006, 10:41 AM
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I would have thought it's just picking up the noise of the clutch engaging/gearbox noise..? Especially as it's OK elsewhere in the rev range..!
I'm sure someone with more knowledge will contribute as to whether this could be the case (or not)..
I'm sure someone with more knowledge will contribute as to whether this could be the case (or not)..
05 October 2006, 02:11 PM
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Assuming the KC you are seeing is being displayed on a data monitor, negative KC is not good as it indicates that the ECU is retarding because it's detecting something it doesn't like.
I recently posted asking about knock correction on a data monitor versus knock activity detected by a knock link. Interesting info.
https://www.scoobynet.com/knocklink-...ock+correction
I recently posted asking about knock correction on a data monitor versus knock activity detected by a knock link. Interesting info.
https://www.scoobynet.com/knocklink-...ock+correction
06 October 2006, 11:24 AM
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Originally Posted by Trap2Terrorist
Assuming the KC you are seeing is being displayed on a data monitor, negative KC is not good as it indicates that the ECU is retarding because it's detecting something it doesn't like.
I recently posted asking about knock correction on a data monitor versus knock activity detected by a knock link. Interesting info.
https://www.scoobynet.com/knocklink-...ock+correction
I recently posted asking about knock correction on a data monitor versus knock activity detected by a knock link. Interesting info.
https://www.scoobynet.com/knocklink-...ock+correction
Interesting link..
T2T, what's your current spec..?
06 October 2006, 03:13 PM
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A noisy release bearing can be picked up by the factory knock sensor and cause the ecu to pull timing during take off. Not sure if it will cause the knocklink to light on off throttle coasting though. Do you know if the bosch sensor is ok or not, is it fitted in the correct place, has it come loose ? Strange that the knocklink sensor seems to be detecting something that the factory one isn't, or the ecu isn't responding to.
You can check for det with det cans as already mentioned. In the absence of det, and with known good knock sensors, I would have it looked at professionally as a knocklink can also be triggered by mechanical problems.
You can check for det with det cans as already mentioned. In the absence of det, and with known good knock sensors, I would have it looked at professionally as a knocklink can also be triggered by mechanical problems.