Closed loop at idle ..

Nistune topics related specifically to the 6303 cpu

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Torque
 

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Closed loop at idle ..

Post by Torque »

I found that during idle the lamda voltage is at about .9V.
Trims are at -9.

If I up the revs to 2000 lambda voltage starts oscillating and trims go to -1 or 0.
(so as it should be)

I brought this up some time ago but still am marvelling what is going on.
Shouldn't the car idle at lamda 1?
Matt
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Re: Closed loop at idle ..

Post by Matt »

From what I know it should only close loop at cruise (not at idle)
Torque
 

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Re: Closed loop at idle ..

Post by Torque »

Ahhhh ... thanks Matt ...
That's exactly my observation.

Why do the fuel trims go up at idle?

I also noticed that trims go up with throttle movement.
Is that some 'enrichment' routine?

And (slightly off topic)
What is AFR MAX/MIN Coefficient?
Matt
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Re: Closed loop at idle ..

Post by Matt »

Nissans implementation of Z32 STFT/LTFT inside consult seem to reflect total enrichment adjustment (not just closed loop) so acceleration enrichment gets factored in when outside closed loop (which is why its not 0% around idle)
Torque
 

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Re: Closed loop at idle ..

Post by Torque »

Is it still valid procedure then to adjust K till trims are as low as possible while in closed loop?
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Re: Closed loop at idle ..

Post by Matt »

When in closed loop it should be fine still to target 0%
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