Overrun Fuel Cut

Any feature requests for the Syvecs Engine Control Systems
Jasper K
Posts: 56
Joined: Fri Aug 15, 2008 1:38 pm
Location: Taiwan

Overrun Fuel Cut

Post by Jasper K » Sun Feb 12, 2012 12:56 pm

I think it would be good to ADD one selector in the Closed Throttle Detection where PPS instead of TPS can be selected. TPS works but can be a bit tricky on DBW cars as the IDLE, etc. is all being controlled by the Butterfly. In my opinion going off PPS in this case would be better and certainly easier. Thanks!

Jasper.

Johnny G
Posts: 26
Joined: Tue Mar 10, 2009 2:38 pm
Location: Liverpool, England
Contact:

Re: Overrun Fuel Cut

Post by Johnny G » Sun Feb 12, 2012 8:37 pm

Definitely.
With my car, I had to have a right play around to get the overrun fuel cut to work, however, it is now. What I did was let the car warm up to full temp and idle, monitoing the TPS (with a 0 position PPS), then look at the TPS read back. Mine, IIRC was at 2.5%.
Then I went to Sensors -> Throttle Position -> Closed Throttle Detection
Window size: 3%
Window size hysteresis: 1%

Then monitor channel "tpsClosed" - and when you increase PPS (and therefore TPS), it should go "CLOSED" -> "OPEN".

Your mileage may vary though.
Cheers,
Johnny
1995 MR2 GTS V6 Turbo
1998 Supra VVTi TT6

ScoobyDuck
Posts: 49
Joined: Mon Aug 17, 2009 3:24 pm
Location: South Uk

Re: Overrun Fuel Cut

Post by ScoobyDuck » Wed Feb 15, 2012 1:38 pm

i had an issue with this also but more in when it resumes.

normally it would resume fueling about 1500 or so but on my car the idle (especially on cold start but also on warm start) would raise far above that (2000+) as an initial blip. this would then cut the fuel leading to all kinds of hunting and horrible unstable hunting in a vain attempt to control things.

making the recovery fueling =~2200 solved things as it never hit this. although now, fueling is still happening on overrun much more than i'd like.

What i'd like to be able to do is to allow it to only cut the fuel after say 6seconds after start, or maybe after ECT>50. maybe both.
maybe i just need to stop it reving so damn hard on crank!

thanks to Ryan for noticing the initial issue.

cheers
Steve

Ryan.g
Syvecs Staff - Caretaker
Posts: 280
Joined: Fri May 30, 2008 3:05 pm

Re: Overrun Fuel Cut

Post by Ryan.g » Sat Feb 18, 2012 10:36 am

Added to Firmware tracker guys as in some cases is useful

Andrearally
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Joined: Mon Jan 23, 2012 6:43 pm
Location: Verona - ITALY
Contact:

Re: Overrun Fuel Cut

Post by Andrearally » Fri Mar 09, 2012 12:08 pm

Can be very usefull to have Overrun ON or OFF for each mapswitch position.

Isn't good to have Overrun ON during ALS or full race map.

Best Regards
Andrea Maselli
www.am-race.com
Personal Blog www.andreamaselli.com

Jasper K
Posts: 56
Joined: Fri Aug 15, 2008 1:38 pm
Location: Taiwan

Re: Overrun Fuel Cut

Post by Jasper K » Wed Mar 14, 2012 10:14 am

^^^ Yes, you are correct. It would be nice indeed to have a individual toggle based on Cal. switch position to Enable/Disable Overrun Fuelcut.

Cheers,

Jasper.

EMS
Posts: 41
Joined: Tue Oct 12, 2010 1:24 pm

Re: Overrun Fuel Cut

Post by EMS » Wed Mar 28, 2012 12:58 pm

+1

CanisLupus
Posts: 6
Joined: Mon Mar 25, 2013 10:56 pm

Re: Overrun Fuel Cut

Post by CanisLupus » Fri Apr 26, 2013 9:06 am

Regarding Overrun Fuel Cut. Can you add a Timer and/or ECT Threshold where it activates? I want to set my Fuel Cut Threshold at 1250rpm(or even lower) and my Cold Start Idle at 1400 for a short time. When i set it like that the RPMs fluctuate like mad as the Fuel Cut occurs. Would be nice to have something like that. Thanks :)

ScoobyDuck
Posts: 49
Joined: Mon Aug 17, 2009 3:24 pm
Location: South Uk

Re: Overrun Fuel Cut

Post by ScoobyDuck » Fri Apr 26, 2013 10:12 am

Exactly the problem i have. have to set it stupidly high >2000 otherwise when you start, or fall back into idle, sometimes it oscillates. Ryan solved the issue by inceasing the leve but 2000 is a bit high / wasteful when you're using the car daily.

Steve

CanisLupus
Posts: 6
Joined: Mon Mar 25, 2013 10:56 pm

Re: Overrun Fuel Cut

Post by CanisLupus » Fri Apr 26, 2013 11:47 am

That's it. The fuel cut works really nice when warm i'm driving the car with the overrun fuel cut set to 1300 now but would like to have the possibility to get the idle higher when cold to get the car warming up faster. :)

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