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Hi iam new on here thank in advane for any information 1,does the knock sensor work in open loop? 2, does the delco 808 go in open loop at WOT .3 if the knock sensor is not workings how much will the ecu advance the ignition timing.4,in open loop what would the preset air fuel ratio be. All the above is on vn v6 Thanks again

The knock sensor works up to around 3600rpm then turns off . If it's broken or unplugged the ecu will pull 10 degrees of timing out everywhere .as for air fuel spends on the tune s1 and 2 are different so are many of the revisions and if you change anything on the car airflow related ie intake or headers or exhaust it will still inject the same amount of fuel it always has so could have any manor of fuel ratios over the intire rpm range .download tunerpro turtles and some bin files out of the stock Holden bin file thread in the Holden aldl ecus section and the matching xdfs out of the stock Holden xdf thread

Thank you that's been great do you know if the ecu on vn v6 goes into open loop at wide open throttle and also what is max spark advance

Max spark advance is a configurable item, generally around 45 degrees by default, but set it to what you need/want.

Yep open loop when load gets above 70kpa all the way to full throttle timing is different in every tune they don't need anymore than 28 degrees up top at full throttle

"Open loop" you are referring to (oxygen sensor to trim fuel) is unrelated to ignition.

There are many different "closed loop" systems as part of the engine management:

-Oxygen sensor as feedback about fuel delivery is one closed loop system. (If the sensor says rich or lean, fuel will be added or deducted as required)

-Knock sensor for feedback about ignition advance is another closed loop system. (If knock is detected advance will be reduced)

-Engine speed as feedback for idle speed control is another closed loop system. (IAC or Ignition advance will be used to maintain the desired idle speed).

The closed loop fuel system will be open loop whenever the desired AFR is not lambda 1.000. (Full throttle will be rich, so it will be open loop). It will also be open loop when other parameters in the particular tune are not met (coolant temp, run time, etc).