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Closed loop Fail-safe for CAN lambda

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Hi, there

Is anyone running full time closed loop for your link G4+?

I wondering is there any fail-safe for it once O2 sensor damage? will it kill my engine since the incorrect fuel compensation?

Any suggestion about it?  Thanks.
 

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Your tune needs to be good enough to run the engine correctly with no oxygen sensor feedback. Then, closed loop lambda should only be making very minor temporary adjustments.

 

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thanks, Confused.

I have good tuned and I running full time closed loop due to the compensation may not very accuracy.

So far, I running full time closed loop very well, the max correction percentage is always less than 3%.

I just not sure about it, if the O2 sensor damage during hevy loading (WOT and high boost), is it will give me a wrong AFR value and trim my fuel to the wrong volume then kill my engine? Or are there any fail safe for it? 
 

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You can set your maximum trim percentage to the maximum modification value you are happy with, for example 5%.

 

This will then never add or remove more than 5% fuel. If the sensor does, for some reason, fail in a way that it is still giving a reading (albeit incorrect), you won't get a massive correction applied.

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If using the Link CAN lambda (or internal Fury/Thunder lambda) there is fail safe logic built in.  

If using a single CAN lambda and it reports an error then Lambda will be displayed/logged as zero and the CLL will be disabled.

If using two CAN lambdas in dual channel mode and one reports an error the CLL will be disabled on that bank only.

If using multiple CAN lambdas and single channel CLL (based on Lambda average), if one sensor reports an error then that sensor will be removed from the Lambda average calculation and CLL will be based on the average of the remaining good sensors.  If all sensors are reporting errors then CLL will be disabled

 

Note if using an ecu with automode you can also turn on 3D trim tables which allows you to specify different min & max trims under different conditions.  For example you could allow CLL to remove 25% fuel under cruise conditions, but no more than 3% at high boost or full throttle. 

CLL is also disabled during any of the lockout conditions, as well as launch control, antilag, over-run fuel cut, accel enrichment active etc.

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