Overrun cutoff Issues

K-Series Programmable ECU installation questions / support issues
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KSeries4Life
Posts: 41
Joined: Fri Mar 14, 2014 7:54 am

Overrun cutoff Issues

Post by KSeries4Life »

KManager 4.3.5.0
KPro4 PRB ECU
K24/K20 swapped 2004 S2000
Magnus Sheet Metal K-Series Intake Manifold
90mm KTuned TB
Injector Dynamics 725
Overrun cutoff manifold pressure set to 12 KPa on low/high cam

My first issue is that "Disable fuel over-run cutoff delay" doesn't seem to work. I've got the box checked, and the ECU has been flashed several times with it checked before these logs were taken. This can be seen in "2018-06-18_4(Overrun Cutoff Issue).kdl"

Second issue I'm having is that it takes almost 1.5 seconds (starting from when I press on the gas pedal) for the injectors to turn back on after an overrun. I'm not seeing anything popping out at me in KManager that would allow me to tweak the conditions to restart the injectors. Can be seen in both logs I attached.
Attachments
2018-06-18_4(Overrun Cutoff Issue).kdl
(222.26 KiB) Downloaded 170 times
2018-06-19_1(Overrun Cutoff Issue).kdl
(151.79 KiB) Downloaded 180 times
06-18.kal
(165.49 KiB) Downloaded 171 times
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Spunkster
Site Admin
Posts: 22745
Joined: Fri Sep 20, 2002 5:06 pm
Location: Hondata

Re: Overrun cutoff Issues

Post by Spunkster »

1) it is not reaching 12 kpa to shut them off.

2) This is probably because it is decelerating and not with the larger throttle body there is not much of a change in vacuum when this is occurring. That would be my best guess.
KSeries4Life
Posts: 41
Joined: Fri Mar 14, 2014 7:54 am

Re: Overrun cutoff Issues

Post by KSeries4Life »

Hello, Thanks for the response.

1) I reflashed my ECU yesterday with an Overrun Cutoff of 18 kpa. There still looks to be an exact time of .5 seconds delay before it goes into overrun, even when going below 18 kpa. This can be seen in the log I attached.

2) Is there anyway you could let me know the exact conditions required to come out of overrun on kpro? I'm trying to smooth out the huge jerk in power I get after getting back on the accelerator after overrun. Is this based on the TPS or MAP sensors? In my logs, I tried several different ways of getting back on the accelerator to see if I can isolate the conditions. For sure, I have ruled out there being any kind of delay like there is when going into overrun (this is regarding the 1.5 seconds in my initial post). I did this by slamming on the accelerator and it basically instantly came out of overrun (seen @ 1:06). The times where I slowly got back on it, I can't definitively say if it was going past a set MAP/TPS value or if it had to do with the rate of change. But, if I were to take a guess, it almost looks like there is a hard coded value of 25 kpa where it comes out of overrun. This can be seen @ 0:49, 1:12, 1:17 and 1:23. Any way to tweak this value if that's the case?
Attachments
2018-06-19_2(Overrun Cutoff Issue).kdl
(1.91 MiB) Downloaded 167 times
06-19.kal
(165.49 KiB) Downloaded 150 times
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Spunkster
Site Admin
Posts: 22745
Joined: Fri Sep 20, 2002 5:06 pm
Location: Hondata

Re: Overrun cutoff Issues

Post by Spunkster »

There is no access to these values in the software and I cannot see what these values are.
KSeries4Life
Posts: 41
Joined: Fri Mar 14, 2014 7:54 am

Re: Overrun cutoff Issues

Post by KSeries4Life »

What about my overrun cutoff delay issue?

Is your response confirming that it is the MAP value that brings it out of overrun?

Do you know if the IACV lets air in during overrun? If so, this might explain some of my issues. I tried using one with the KTuned 80mm setup w/IACV, but it let way too much air in to idle properly.
KSeries4Life
Posts: 41
Joined: Fri Mar 14, 2014 7:54 am

Re: Overrun cutoff Issues

Post by KSeries4Life »

So last night I decided to make some tweeks to my knock sensitivity (I've got some loud cams) and while I was in there, I figured I would uncheck "Disable fuel over-run cutoff delay" since it didn't seem to be working any way. Looking at the logs I took this morning, I noticed there is no longer a .5 second delay before entering the overrun conditions I have set...

I'm happy I can now toggle this setting, but is this the way this check box is supposed to work? The way it's worded, I'm getting the opposite effect.
Attachments
2018-06-22_1(Overrun Cutoff Issue).kdl
(3.08 MiB) Downloaded 171 times
06-21.kal
(165.45 KiB) Downloaded 156 times
Grise
Posts: 1
Joined: Thu Jun 28, 2018 2:42 am

Re: Overrun cutoff Issues

Post by Grise »

That's very peculiar, KSeries4Life. But if it's working, that's awesome. It was a stroke of genius to uncheck that box and see what happens. haha
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