CLL Disabling at Low TPS positions

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ciphermonk
Posts: 23
Joined: Fri Nov 04, 2016 8:47 pm

CLL Disabling at Low TPS positions

Post by ciphermonk »

So I have a weird issue that I'm trying to figure out. If I push down accelerator and then lift off, Closed loop lamda is being disabled temporarily and Lamda spikes to 2.7 while this happens. I've tried adding fuel to 200 - 600 mb area of the map where this happens and it makes no difference.

Log at: https://www.dropbox.com/s/guxwr7djrv2du ... 88.SD?dl=0

Just move to a point where you see lambda spike and shortly before that you'll see that CLL is disabled. A time point 16:23:59 has an instance.

Any ideas?
Slowie
Posts: 123
Joined: Thu Jan 17, 2013 7:30 am

Re: CLL Disabling at Low TPS positions

Post by Slowie »

Are you experiencing any driveability issues? From looking at the log, it just seems like the overrun fuel cut is kicking in at the point in time you mention.
ciphermonk
Posts: 23
Joined: Fri Nov 04, 2016 8:47 pm

Re: CLL Disabling at Low TPS positions

Post by ciphermonk »

Yes. It creates a slight bucking feeling after every acceleration / stab of the throttle. I'm not sure if it's the overrun fuel cut because the "Engine Speed" parameter is set at 7000 RPM on my car.

This happens while driving the car at a steady speed and then trying to accelerate.
stevieturbo
Posts: 1321
Joined: Sun Dec 07, 2008 2:04 pm

Re: CLL Disabling at Low TPS positions

Post by stevieturbo »

Not sure whether it will impact on it, but very rarely is the ecu detecting closed throttle....despite what it would appear in the log you have let off the pedal.

Check this is set up correctly.

If you have overrun fuel cut off set at 7000rpm....then it will only be active above 7000rpm.

And in the areas where lambda goes high, closed loop appears disabled in some areas, and base fuel values seem very low.

What thresholds do you have for closed loop to actually work ?

IMO as a test, turn closed loop control off and get fueling close to right with no corrections taking place. If the fuel table is miles off, or closed loop settings are not good, you can be chasing your tail.
Remove one of the variables.
ciphermonk
Posts: 23
Joined: Fri Nov 04, 2016 8:47 pm

Re: CLL Disabling at Low TPS positions

Post by ciphermonk »

Thanks Stevie. I haven't changed the CLL settings other than what came in the base map. I'll disable CLL and get the open loop map as close as possible like you said.

The TFC Disable Threshold is set to .200ms
Lambda Error Disable Threshold is set to .50 lambda

I probably have a lean spot in my fuel table and that's probably far enough off that it's causing CLL to disable itself because it can't correct enough.
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