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AFR 10,7:1 spikes in closed loop
Posted: Sun Jul 31, 2011 9:23 am
by retroid
EUDM CTR EP3
Hondata K pro / PLX wideband (to ELD, wire cut, resistors removed)
my spec is:
RBC + GruppeM
KiddRacing 4-2-1 race header (decat)
BuddyClub ProSpec 65mm
The car is running fine but I have very rich spikes after changing gears or intermitate acceleration and deceleration. Is this normal in closed loop? Open loop seems fine.
I have another issue after could starts (closed loop), when I try to put very very light throttle TPS 4% the AFR goes wide lean and the car hesitate, almost stall. If I leave the pedal TPS 0%) or accelerate further the AFR turnes in to the "range"
many many thanks for help!
here are the logs:
Re: AFR 10,7:1 spikes in closed loop
Posted: Mon Aug 01, 2011 9:40 am
by Spunkster
What sensor are you running closed loop from?
Re: AFR 10,7:1 spikes in closed loop
Posted: Mon Aug 01, 2011 2:53 pm
by retroid
I'm running the oem sensor (narrow band).
many thanks
Re: AFR 10,7:1 spikes in closed loop
Posted: Mon Aug 01, 2011 3:09 pm
by Spunkster
post your calibration as well
Re: AFR 10,7:1 spikes in closed loop
Posted: Mon Aug 01, 2011 8:24 pm
by retroid
the calibration:
Re: AFR 10,7:1 spikes in closed loop
Posted: Tue Aug 02, 2011 10:25 am
by Spunkster
Why are your MAP and TPS changing continuously?
Re: AFR 10,7:1 spikes in closed loop
Posted: Tue Aug 02, 2011 11:34 am
by retroid
on this part?
I was hitting the gas pedal, just to evidence the low AFR spikes on very fast TPS changings. Is this normal? A small amount of unburned gas hits the exhaust and generate this "short" AFR figures?
Re: AFR 10,7:1 spikes in closed loop
Posted: Tue Aug 02, 2011 12:12 pm
by Spunkster
There may be spikes at throttle tip in, this is pretty normal
Re: AFR 10,7:1 spikes in closed loop
Posted: Tue Aug 02, 2011 1:30 pm
by retroid
The spikes occurs during abrupt tip-out, on mine.
Re: AFR 10,7:1 spikes in closed loop
Posted: Tue Aug 02, 2011 1:44 pm
by Spunkster
Has this been professionally tuned?
Re: AFR 10,7:1 spikes in closed loop
Posted: Tue Aug 02, 2011 2:15 pm
by retroid
yes, on street and dyno (not by me of course) :)
car runs ok, I'm only triyng to understand the nature of these "sparks".
a better zoom look. I think there are the inertial gases resulting from the abrupt tip-out, so normal condition....
Re: AFR 10,7:1 spikes in closed loop
Posted: Tue Aug 02, 2011 2:29 pm
by Spunkster
That is tuning related. Look at the short term fuel trim right before you let off and you will see that it is adding up to 14% fuel and then you suddently let off it still wants to add that fuel for a split second. I would have your tuner take a look at this.
Re: AFR 10,7:1 spikes in closed loop
Posted: Wed Aug 03, 2011 12:06 am
by retroid
sorry but I can't find that specific moment with the short fuel trim issue.
is it on the first datalog? i need to study this "to death" cause I'm confused....
many thanks for the help!
Re: AFR 10,7:1 spikes in closed loop
Posted: Wed Aug 03, 2011 9:30 am
by Spunkster
Change your graphs to show short term fuel trim and you will see it.
Re: AFR 10,7:1 spikes in closed loop
Posted: Wed Aug 03, 2011 2:55 pm
by retroid
Ok! I was looking at the other datalog. the specific moment:
so, in a "perfect condition" once the TPS goes instant from 100% to 0, the S.TRIM also should decrease instantly?
I found another strange thing. I have the emissions error checking disabled (OBD II, secO2, PA , etc) but the secO2 enabled.... Is this ok?
many thanks! I started to study all the kmanager/k pro training and now I begin to understand it much better.
Thanks for posting such an important learning informations. The automotive and DIY culture in the US in outstanding!