Kieran Posted November 10, 2013 Report Share Posted November 10, 2013 Hi guys, my ECU (G4 Extreme red) is set to flash the CEL when knock exceeds 500, which aligns with the knock control configuration as it was set up using a pair of known good knock headphones. I've noticed that after the upgrade to FW 4.9.8, the CEL has been flashing intermittently at unusual times, e.g. during cruise conditions - 50-80 kPa MAP, steady throttle, under 3000rpm; or while decelerating on overrun fuel cut. I've checked to make sure nothing has come loose on or around the engine that could be causing noise, the car is a road car so it still uses all of the rubber engine, drivetrain and exhaust mounts. The knock sensor is a donut type provided by Torque Performance to suit the ECU and is about 18 months old. The mapping has not changed and is still operating with the correct o2 readings and ignition timing. So, I'm struggling to identify any potential changes that could have caused this, other than the firmware update. Have there been any changes to the way knock detection is done in FW 4.9.8? Quote Link to comment Share on other sites More sharing options...
Scott Posted November 11, 2013 Report Share Posted November 11, 2013 Hi Kieran, I have had a look through the revisions notes from version 4.9.3 and 4.9.8, the only change I can see to do with knock control was the removal of the old 'analog' mode. Being that your ECU is a Red Xtreme I take it you are using the 'Knk Internal' mode? It may be worth setting up your PC or ECU logging and recording a log of this so you can see under what conditions the CEL is coming on, and if it should be. Regards, Scott Quote Link to comment Share on other sites More sharing options...
Kieran Posted November 16, 2013 Author Report Share Posted November 16, 2013 Yep, I'm using the internal knock detection capability. I'll try to capture the logs. Quote Link to comment Share on other sites More sharing options...
Kieran Posted January 21, 2014 Author Report Share Posted January 21, 2014 OK, I finally got around to logging this. Attached is an Excel spreadsheet of the log, the rows where knock has been detected are colour highlighted. I can upload the LLG file if you want, but it's quite large at 15MB as I let the car idle for a while in order to capture the symptom. Quote Link to comment Share on other sites More sharing options...
Scott Posted January 22, 2014 Report Share Posted January 22, 2014 Hi Kieran, There is now a new PCLink/Firmware release for the G4 ECUs, the version number is 4.9.9. There has been some changes to the Knock visibility. I'm not sure how this would affect you, but it may be worth upgrading. If this does not help, please send your log through to [email protected]. It may be worth attempting to zip the file first to lower its size. Scott Quote Link to comment Share on other sites More sharing options...
Kieran Posted January 22, 2014 Author Report Share Posted January 22, 2014 OK, I'll apply the firmware update and re-test. Thanks! Quote Link to comment Share on other sites More sharing options...
Kieran Posted February 4, 2014 Author Report Share Posted February 4, 2014 A couple of tanks of gas since the firmware was upgraded to ver 4.9.9, and the CEL light hasn't flickered once. Thanks Scott. Quote Link to comment Share on other sites More sharing options...
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