Fuel overrun cutoff

K-Series Programmable ECU installation questions / support issues
Post Reply
fonzeka
Posts: 78
Joined: Thu Feb 11, 2016 4:15 am
Location: Sweden

Fuel overrun cutoff

Post by fonzeka » Tue May 14, 2019 1:40 pm

I'm not sure if I have a real problem but I'm wondering if there's always going to be a delay before the injectors are shut off?
All or almost every time I let off the throttle I'm seeing a full rich condition and I can see the injectors are still spraying.
I haven't thought to much about it before but I was thinking it might wash out cylinders or just use unnecessary fuel so it would be nice to fix it.
I have "disable fuel over-run cutoff delay" box ticked and I have also checked and done some small adjustments under Overrun Cutoff MAP settings.
This didn't seem to make much difference though.

One other small question that probably is not related but I find very weird is the Rev Limit sensor.
What does this "sensor" actually relate to?
It seems to be active very often and I can't really find a logical pattern.

Car is a S2000 with ITB's, ID1050x and is running E85.
Kpro4
Kmanager version 4.4.1

Log showing the behavior, to large to upload on this forum.
https://www.dropbox.com/s/nzetfzpgsmjry ... .kdl?raw=1
Attachments
tune.kal
(162.61 KiB) Downloaded 15 times

User avatar
Spunkster
Site Admin
Posts: 17643
Joined: Fri Sep 20, 2002 5:06 pm
Location: Hondata
Contact:

Re: Fuel overrun cutoff

Post by Spunkster » Tue May 14, 2019 5:00 pm

You have ITB's, why are you not using the Alpha-N settings which are specifically for use with ITB's?

fonzeka
Posts: 78
Joined: Thu Feb 11, 2016 4:15 am
Location: Sweden

Re: Fuel overrun cutoff

Post by fonzeka » Tue May 14, 2019 10:58 pm

Because MAP based works pretty good and was much easier to tune.
Would an alpha-n tune make a difference regarding this specific issue?

User avatar
Spunkster
Site Admin
Posts: 17643
Joined: Fri Sep 20, 2002 5:06 pm
Location: Hondata
Contact:

Re: Fuel overrun cutoff

Post by Spunkster » Wed May 15, 2019 9:08 am

Alpha-N is the recommended tuning method for ITB's and will probably be much smoother and run better.

fonzeka
Posts: 78
Joined: Thu Feb 11, 2016 4:15 am
Location: Sweden

Re: Fuel overrun cutoff

Post by fonzeka » Wed May 15, 2019 10:07 am

I know, but I have a very effective vacuum block which you could probably see in the log so please disregard this.
What is the minimum delay for the fuel overrun cutoff? Is half a second normal or should it be lower?
Also if you could answer my question about the rev limit sensor that would be great.

User avatar
Spunkster
Site Admin
Posts: 17643
Joined: Fri Sep 20, 2002 5:06 pm
Location: Hondata
Contact:

Re: Fuel overrun cutoff

Post by Spunkster » Thu May 16, 2019 10:04 am

There is no rev limiter sensor. If it is rev limiting then it is doing so for a reason.

You can trim your datalogs by right clicking and selecting a new start and end point and then re-saving to make the file smaller and easier to show where an issue occurs.

fonzeka
Posts: 78
Joined: Thu Feb 11, 2016 4:15 am
Location: Sweden

Re: Fuel overrun cutoff

Post by fonzeka » Thu May 16, 2019 2:30 pm

Thanks for the tip on trimming the logs.
I made it much smaller now and it should be pretty clear now if you check what is happening at 1:02 1:20 1:31 mark
Please check the behavior on the "rev limit sensor" as well, every time the injectors shut off it seems the rev limiter is ON.

And yes this "sensor" does exist, this is from your kmanager change history:
V4.3.5 (13 Feb 2018)
· Added rev limiter sensor to datalogging.
Attachments
log.kdl
(3.34 MiB) Downloaded 10 times

User avatar
Spunkster
Site Admin
Posts: 17643
Joined: Fri Sep 20, 2002 5:06 pm
Location: Hondata
Contact:

Re: Fuel overrun cutoff

Post by Spunkster » Thu May 16, 2019 5:03 pm

More than likely your TPS is too far out of adjustment. I would recommend manually adjusting it so that the correction when calibrating is as close to zero as possible. This probably has to do with both issues. The sensor list is just a list of all datalogged parameters. There is no actual sensor for rev limits.

Post Reply