NefMoto

Technical => Tuning => Topic started by: envisible on September 10, 2013, 11:19:28 PM



Title: DEKA 870cc and bad idle
Post by: envisible on September 10, 2013, 11:19:28 PM
Hi guys.

I try to use 870cc siemens deka injectors on my 2L stroker( AMB based). Fuel system is returnless, stock FPR. Mafless.

ddillenger helps me to locate TEMIN and KRKTE

TEMIN 14DA6 16 BIT FACTOR 0.002667
KRKTE 1F82A 16 BIT FACTOR 0.000167

And I use KRKTE calculator and set it to 0.0363

But now, on cold engine I have very rich mixture and LTFT on idle is about -9.8%. LTFT on partial load is 0.2%.
Injection time on idle is 1.56ms.
Whats wrong with me? :)
Please don't blame mafless.

Here is flash I use and mappack with just scaling maps.


Title: Re: DEKA 870cc and bad idle
Post by: IamwhoIam on September 11, 2013, 01:59:56 AM
how do you think your ECU can calculate correctly the amount of fuel that is supposed to be injected under idle/part throttle conditions?


Title: Re: DEKA 870cc and bad idle
Post by: ddillenger on September 11, 2013, 02:53:32 AM
Not to mention TVUB

 :o


Title: Re: DEKA 870cc and bad idle
Post by: Rabbid on September 11, 2013, 03:34:15 AM
Whats your stock FKKVS doing? I've seen some stuff in stock tables add or remove loads of fuel around idle.

But unless your MAFless calibration worked perfectly on stock injectors then you might need to revisit the air mass amounts you're giving it.


Title: Re: DEKA 870cc and bad idle
Post by: envisible on September 11, 2013, 04:02:57 AM
how do you think your ECU can calculate correctly the amount of fuel that is supposed to be injected under idle/part throttle conditions?

By wideband 02 sensor?

TVUB is changed according datasheet http://siemensdeka.com/specsheets/FI114992cs.jpg


Whats your stock FKKVS doing? I've seen some stuff in stock tables add or remove loads of fuel around idle.

But unless your MAFless calibration worked perfectly on stock injectors then you might need to revisit the air mass amounts you're giving it.

This injectors never runs with MAF..

Does 1.56ms opening time is OK for this injectors on idle?
I think I need to adjust FKKVS map, but I sorry, I don't understand this map so good.. Could you give me some advice or help to correct it?


Title: Re: DEKA 870cc and bad idle
Post by: julex on September 11, 2013, 06:46:38 AM
By wideband 02 sensor?

TVUB is changed according datasheet http://siemensdeka.com/specsheets/FI114992cs.jpg


This injectors never runs with MAF..

Does 1.56ms opening time is OK for this injectors on idle?
I think I need to adjust FKKVS map, but I sorry, I don't understand this map so good.. Could you give me some advice or help to correct it?

How did you calculate TVUB? let us know exactly since it is most likely calculated wrong... and that sheet has tons of errors. Some values don't make any sense...

Edit: and what's your pulse width at idle, without TVUB added in. Or share what final pulse width is and TVUB values as well as exact voltage at that moment so I can derive. These dekas have a minimum operational pulse width of 0.599ms which is I believe more than what your engine idles as and this would cause near idle problems.


Title: Re: DEKA 870cc and bad idle
Post by: IamwhoIam on September 11, 2013, 08:11:54 AM
So a wideband O2 sensor also acts as an air flow sensor? funny that, I would have never thought about something like this.


Title: Re: DEKA 870cc and bad idle
Post by: nyet on September 11, 2013, 09:26:38 AM
So a wideband O2 sensor also acts as an air flow sensor? funny that, I would have never thought about something like this.

That isn't what he's saying :P


Title: Re: DEKA 870cc and bad idle
Post by: envisible on September 12, 2013, 04:59:29 AM
TEMIN was found incorrectly
Right adress is 1F824.
And with KRKTE 0.032 it gives me good idle and throttle response on cold engine. LTFT additivi is -2% now.

But I agree, the MAF is necessary. RS4?



Title: Re: DEKA 870cc and bad idle
Post by: ddillenger on September 12, 2013, 11:17:48 AM
TEMIN was found incorrectly
Right adress is 1F824.
And with KRKTE 0.032 it gives me good idle and throttle response on cold engine. LTFT additivi is -2% now.

But I agree, the MAF is necessary. RS4?



RS4 MAF is good if you intend on exceeding 320g/s. Under that, the S4 bosch is a good choice.


Title: Re: DEKA 870cc and bad idle
Post by: hammersword on September 12, 2013, 04:20:29 PM
What are you talking guys???? lambda reads airflow? lol

When the MAF is deactivated you run in secondary load mode =  Throttle + MAP! When the engine is in idle the load 100% is calculated via throttle and in software there are many maps for airflow calculation in function of Throttle angle, throttle size, engine displacement!
Installing bigger throttle will kill your airflow calculation if you miss to recalibrate all the Throttle air flow model in the ECU and you will face too lean AFRs and too high positive fueltrims!

I do for many years MAFless setups when the turbo inlet is bigger than 80mm like PTE 6262 or 6765 in 20VTs with injectors ID1000 or ID1200 without having any issue with fueltrims, idle and fueling at all.... Of course for finetuning are needed maaaany files and hours, if you are looking for the perfection which for me is the most important.
KRKTE: I have posted a calculator .xls in NEFMOTO forum
TVUB (easy to be found over the internet for DEKAs and IDs)
FKKVS (The most important and smartest map in Motronics)
TEMIN: 0.5ms is fine for 870cc @ 3bar

cheers,
Fotis


Title: Re: DEKA 870cc and bad idle
Post by: silentbob on September 18, 2013, 10:13:05 PM
......................
FKKVS (The most important and smartest map in Motronics)
......................

Map for fixing shitty calibrations in other areas would be a more precise description for this one.


Title: Re: DEKA 870cc and bad idle
Post by: prj on September 19, 2013, 03:10:26 AM
When the MAF is deactivated you run in secondary load mode =  Throttle + MAP!
ME7 does not have MAP.


Title: Re: DEKA 870cc and bad idle
Post by: catbed on September 19, 2013, 05:25:14 AM
What are you talking guys???? lambda reads airflow? lol

When the MAF is deactivated you run in secondary load mode =  Throttle + MAP! When the engine is in idle the load 100% is calculated via throttle and in software there are many maps for airflow calculation in function of Throttle angle, throttle size, engine displacement!
Installing bigger throttle will kill your airflow calculation if you miss to recalibrate all the Throttle air flow model in the ECU and you will face too lean AFRs and too high positive fueltrims!

Secondary load has nothing to do with MAP sensor. It is alpha-n with o2 feedback.


Title: Re: DEKA 870cc and bad idle
Post by: julex on September 19, 2013, 10:19:16 AM
Map for fixing shitty calibrations in other areas would be a more precise description for this one.

Amen. Mine is all 1.00 and the car runs great.


Title: Re: DEKA 870cc and bad idle
Post by: NOTORIOUS VR on September 20, 2013, 06:37:13 AM
LOL


Title: Re: DEKA 870cc and bad idle
Post by: elRey on September 20, 2013, 06:59:00 AM
TEMIN was found incorrectly
Right adress is 1F824.
And with KRKTE 0.032 it gives me good idle and throttle response on cold engine. LTFT additivi is -2% now.

But I agree, the MAF is necessary. RS4?

So are your idle issues fixed now that you have correct TEMIN address?  What were your final values for TEMIN and TVUB?


Title: Re: DEKA 870cc and bad idle
Post by: envisible on November 12, 2013, 12:32:09 PM
So are your idle issues fixed now that you have correct TEMIN address?  What were your final values for TEMIN and TVUB?

Hi. My TVUB now is 1,6367 0,9478 0,7476 0,5901 0,4406 and KRKTE 0.032
I have add -5% and mult 1.6%
And 1.56ms injecting time in VCDS.
I think I need to reduce TVUB, but since I changed it from first configuration, it has no effect on injection time. What wrong?
Thanks