General question: Engine is cold = jerki on slow speed-up only on low rpm

FlashPro questions & answers specific to the FN2 European Civic Type R
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typer86
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Joined: Sun Oct 28, 2012 3:17 pm

General question: Engine is cold = jerki on slow speed-up only on low rpm

Post by typer86 » Fri May 22, 2015 2:28 pm

Hi Hondata,

If the engine is cold (in the morning) in low rpm and speed-up it is a little bit jerki to drive. But if I reach ~2.600 rpm all is normal.
Any idea which option I must tune to fix the "jerki" speed-up? I think all is default at the moment because I don't know which setting I must adjust.

It is this option?
Fuel > Air temperatur compensation
>> Air temperature fuel compensation low flow
IAT (°C) = defaults...
Trim (%) = 0.0 (default)

>> Air temperature fuel compensation medium flow
IAT (°C) = defaults...
Trim (%) = 0.0 (default)

>> Air temperature fuel compensation high flow
IAT (°C) = defaults...
Trim (%) = 0.0 (default)

MAP:
FN2_Rotrex_v8_final.fpcal:
https://www.hondata.com/forum/download/file.php?id=7490

Thanks for help and give me the tip.

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Hondata
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Re: General question: Engine is cold = jerki on slow speed-up only on low rpm

Post by Hondata » Fri May 22, 2015 3:36 pm

Don't change the fuel compensation tables without determining if the main fuel tables are correctly tuned and your fuel trims are low. If you post a datalog of the problem then we'll look at it.
Hondata

typer86
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Joined: Sun Oct 28, 2012 3:17 pm

Re: General question: Engine is cold = jerki on slow speed-up only on low rpm

Post by typer86 » Sun May 24, 2015 12:54 pm

Hi Hondata,

see attached files below.
Thanks for help.
Attachments
cold_speed_up.fpdl
(305.14 KiB) Downloaded 92 times
FN2_Rotrex_v11.fpcal
(16.26 KiB) Downloaded 87 times

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Hondata
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Re: General question: Engine is cold = jerki on slow speed-up only on low rpm

Post by Hondata » Sun May 24, 2015 6:05 pm

The fuel trims indicate that the tuning is rich by about 10%. I'd fix that first. If it runs ok with AFM tuning as it is then I'd first check that the AFM housing is secure and there are no leaks around the air flow meter. Sometimes even a small rotation will make is read differently. Then I'd either apply a fuel trim or re-tune the AFM table to reduce the fuel.
Hondata

typer86
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Joined: Sun Oct 28, 2012 3:17 pm

Re: General question: Engine is cold = jerki on slow speed-up only on low rpm

Post by typer86 » Tue May 26, 2015 12:36 am

Thanks for your answer.
Ok I will check the fuel and I will re-test again.
The air intake to the supercharger is stock - normally all is secure and closed (tight?) correctly.
Only a Scoop-in after the airbox is installed to get cold fresh air.

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R-12914
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Location: Germany/Bavaria

Re: General question: Engine is cold = jerki on slow speed-up only on low rpm

Post by R-12914 » Tue May 26, 2015 12:52 am

typer86 wrote:Thanks for your answer.
Ok I will check the fuel and I will re-test again.
The air intake to the supercharger is stock - normally all is secure and closed (tight?) correctly.
Only a Scoop-in after the airbox is installed to get cold fresh air.
The scoop-in is installed before the airbox!
Do you have installed the scoop-in before the supercharger-conversion or after the supercharger-conversion?
Komotec have tuned your car?
The tuning from Komotec/Honda Reis are very bad!
I would suggest a fully retune by a good tuner like Vitviper for example!
Last edited by R-12914 on Fri May 29, 2015 12:51 am, edited 1 time in total.
2008 Honda Civic TypeR FN2
Rotrex C30-94 supercharged with relocated IAT
Powered by ASNU 092/FP330E fuel pump & ASNU 090/750cc fuel injectors
------------------------
ECU: 37820-RSP-E03
Flashpro: FP-SI-INT-21153
Software: 3.4.7.0
Firmware: 169

typer86
Posts: 315
Joined: Sun Oct 28, 2012 3:17 pm

Re: General question: Engine is cold = jerki on slow speed-up only on low rpm

Post by typer86 » Fri May 29, 2015 12:29 am

Yes I will contact him soon. Before I will damage the engine.
I don't know which settings I must increase/decrease to make the engine lean/rich in MAF setup. :-(
So I will pay money again again and again.........

nunoctr
Posts: 170
Joined: Tue May 16, 2006 12:29 pm

Re: General question: Engine is cold = jerki on slow speed-up only on low rpm

Post by nunoctr » Tue Jun 02, 2015 3:43 pm

Send me your calibration and 2 datalogs, one wot and one normal driving.
I will fix your fuel in a afm calibration
nunobmg@hotmail.com

User avatar
R-12914
Posts: 352
Joined: Sun Dec 01, 2013 12:13 pm
Location: Germany/Bavaria

Re: General question: Engine is cold = jerki on slow speed-up only on low rpm

Post by R-12914 » Wed Jun 03, 2015 2:25 am

I have been keeping an eye on the datalogs and the map from him.
I think the s-trim is very far in the basement!

A retune at least the fuel in part throttle is necessary!
2008 Honda Civic TypeR FN2
Rotrex C30-94 supercharged with relocated IAT
Powered by ASNU 092/FP330E fuel pump & ASNU 090/750cc fuel injectors
------------------------
ECU: 37820-RSP-E03
Flashpro: FP-SI-INT-21153
Software: 3.4.7.0
Firmware: 169

typer86
Posts: 315
Joined: Sun Oct 28, 2012 3:17 pm

Re: General question: Engine is cold = jerki on slow speed-up only on low rpm

Post by typer86 » Thu Jun 04, 2015 10:41 pm

Good morning all.

Yesterday I spent a lot of time to find to adjust the S.Trim setting in cold conditions in AF calibration.
The same problem occurs on my finial cal from komotec and from R-12914 (thanks again for your help!).

4 thinks adjusted:
- "water temperatur ignition retard" set all values from 15 to 0 - very important setting!
This setting eliminates the jerking if eninge is cold.

- Fuel Temperature Compensation:
> Water temperature fuel compensation cranking:
>> ECT (C°) 82°: set to: -80,9 = Better start if engine is hot
>> ECT (C°) 102°: set to: -81,1 = Better start if engine is hot

- VTC Parameters:
> Use VTC tables upon decel fuel cut = activated
>> Cam angle low: cam angle values adjusted to smooth shifting in low rpm. (Before two tables was set to zero lagging after shift in low boost was the result)

- Throttle:
Better course in throttle plate from mid to high range

- Ignition > Individuel cylinder ignition trim
> Cylinder 2, 3 set to -1

Edit:
Calibration and Datalogs attached

@ Hondata please check if tuned OK.
Maybe the individual cylinder ignition trim could be advanced for cylinder 1 or 4 but i am not sure.

Thanks for all!
Driving with this calibration is very smooth in city and powerfull for a quick sprint!
Attachments
R-22837_MAF_Rotrex_FN2-v4_final.fpcal
(16.36 KiB) Downloaded 83 times
datalog0007.fpdl
20 minutes driving
(2.45 MiB) Downloaded 81 times
datalog0006.fpdl
3rd gear pull
(80.47 KiB) Downloaded 72 times

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