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Old 03-13-2006, 08:50 PM   #1
TravisSTi
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Default When UTEC detects knock?

I had a question on how the UTEC detects knock. Does it detect knock all the time but only correct it when the UTEC is running timing? I'm wondering if I'm getting knock when the ECU has control of the timing. Will the UTEC's logs see a knock (take a knock count) under ECU control and do nothing about it? Or when ECU has control ignore knock totally, detection and reaction?

For instance if I knock at 2000rpm in the 0% load column just cruising down the highway with ECU controlling timing/fuel/boost will I see it in my Knock count column of the #1 log?

Thanks

Travis
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Old 03-14-2006, 10:35 AM   #2
ride5000
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Quote:
Originally Posted by TravisSTi
I had a question on how the UTEC detects knock. Does it detect knock all the time but only correct it when the UTEC is running timing? I'm wondering if I'm getting knock when the ECU has control of the timing. Will the UTEC's logs see a knock (take a knock count) under ECU control and do nothing about it? Or when ECU has control ignore knock totally, detection and reaction?

For instance if I knock at 2000rpm in the 0% load column just cruising down the highway with ECU controlling timing/fuel/boost will I see it in my Knock count column of the #1 log?

Thanks

Travis
travis,

the utec is always "listening" for knock. it will flash the CEL and display the severity of the knock in the logs whenever the knock signal exceeds your programmed thresholds.

however, it will only pull timing if it is in control of timing. ie, you must be above your TPS threshold, AND you must not have ECU in your timing map for the load cell active when the knock was sensed.

hth
ken
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Old 03-14-2006, 11:52 AM   #3
Freon
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I do believe if you get knock when the UTEC is in control, it will still affect your IAM if that is what you are asking. I don't think the UTEC cuts off the signal to the ECU at any time. While the UTEC won't "tell" the ECU to pull timing, the ECU is always listening and deciding for itself how good your gas and tune are.

The ECU and UTEC handle knock differently. The UTEC has some sort of threshold and does it by count. The ECU does it by voltage level. They can and will disagree about knock events.

If you look at your logs and you get a good 3 count according to your UTEC, you will see the "ECU Ign#1" timing also goes down. It is clearly reacting to the same knock even when the UTEC is in open loop. Again, they sometimes disagree especially on 0 and 1 counts, but they almost always agree on the bigger counts.
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Old 03-14-2006, 01:28 PM   #4
ride5000
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to add to what freon points out, the utec may pick up events that the oem ecu does not. actually, from my experience, it SHOULD if the thresholds are set properly. i actually use that disparity to determine the severity of the knock--if the utec sees it and the oem ecu doesn't, then it was pretty low level.
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