NefMoto

Technical => Tuning => Topic started by: aef on September 02, 2014, 01:23:42 AM



Title: jerking engine with AC on
Post by: aef on September 02, 2014, 01:23:42 AM
Hi,

i am trying to find a solution for my jerking shaking engine when air condition is on at idle.
we are talking about a 1.8t AMK S3 with 2L displacement and k04-064 turbo. Single piece flywheel from sachs with 02m gearbox.
i checked several things, block 50 shows ac on and off so communication between AC and ecu is okay.
fuel trims are okay with 1.3% off at idle. rpm should be 840 and is bouncing between 820-850 (at block 50).
Engine is build freshly and there shouldnt be a leak.

from what i read KFMRES could be the solution but i do not understand if this is related to my displacement or the lighter flywheel.

i will attach a log, right after coldstart, later today




Title: Re: jerking engine with AC on
Post by: nyet on September 02, 2014, 09:37:49 AM
Yes, likely you will need slightly more idle torque reserve with a light flywheel.


Title: Re: jerking engine with AC on
Post by: aef on September 02, 2014, 12:11:22 PM
Can someone please assist me in finding KFMRES?

Attached two logs right after cold start, but not until 90°C Water :/

I switched AC on and off.



Title: Re: jerking engine with AC on
Post by: aef on September 03, 2014, 05:03:09 AM
I found it with the help of a friend
X-axis is a little bit different and not that accurate.
Is this normal with ME7.1 -> 7.5



Title: Re: jerking engine with AC on
Post by: aef on September 03, 2014, 11:07:41 AM
I copied the values from KFMRESK to KFMRES and couldnt notice a difference.
Will try tomorrow with cold engine.

the problem i would like to fix:
Cold car runs batch-wise or crinkly or undulated or wavelike... i cant find the right english word  :'(
Its better if AC is turned off.
Its not running smooth like when its warm.

Will have to see if i changed the right map.


Title: Re: jerking engine with AC on
Post by: nyet on September 03, 2014, 11:25:15 AM
If the flywheel is light enough, no amount of additional idle torque will fix the problem.

Will have to look into the idle PID itself and/or increase idle speed.


Title: Re: jerking engine with AC on
Post by: aef on September 03, 2014, 11:31:47 AM
The problem shouldnt be the flywheel because its often used from alot people.
http://www.darksidedevelopments.co.uk/products/sachs-race-single-mass-flywheel-smf-clutch-kit-for-vw-02m-6-speed.html

and it shouldnt be so lightwight

i will check tomorrow and think about what to log...


Title: Re: jerking engine with AC on
Post by: nyet on September 03, 2014, 11:42:03 AM
The problem shouldnt be the flywheel because its often used from alot people.
http://www.darksidedevelopments.co.uk/products/sachs-race-single-mass-flywheel-smf-clutch-kit-for-vw-02m-6-speed.html

and it shouldnt be so lightwight

i will check tomorrow and think about what to log...

Then you may have another issue with idle; possibly fuel related or vac leak, or something along those lines.


Title: Re: jerking engine with AC on
Post by: aef on September 03, 2014, 12:18:43 PM
Fuel trims and idle rpm is Perfect


Title: Re: jerking engine with AC on
Post by: aef on September 05, 2014, 07:13:25 AM
I copied the values from KFMRESK to KFMRES and couldnt notice a difference.
Will try tomorrow with cold engine.

Made it even worse....ill have to understand the table first :/


Title: Re: jerking engine with AC on
Post by: nyet on September 05, 2014, 09:33:05 AM
I copied the values from KFMRESK to KFMRES and couldnt notice a difference.

Err. Ya, about that: probably not the way to "fix" it.

One of those is for clutch in, other is clutch out (forgot which is which).

copying them over is probably not going to fix anything...


Title: Re: jerking engine with AC on
Post by: aef on September 05, 2014, 09:41:56 AM
Yes... The One with K and bigger Values is pressed clutch.
It was just a try.


Title: Re: jerking engine with AC on
Post by: aef on September 08, 2014, 12:24:28 PM
okay i dived a little bit deeper into this...

the topic is wrong here. its not AC related and has nothing todo with KFMRES.

With cold or warm car, with clutch in or out, with KFMRES original or +60% my ignition angle is dancing around.
i tried different KFMRES maps today. i chanced the whole map to 110%, 120, .... 160% from original but my problem was still there.
changing the KFMRES to 160% resulted in +3% load at idle.

So i learned a little bit about this torque reserve which was worth it.

car has a displacement to 2L and my ignition angle is dancing around between -5° and +9°
so the question is: why? and is this the problem or the result of another problem?

-fueling is perfect
-eskonf i okay (rearO2, secondary air deleted)
-KUMSRL and KISRM fixed for 2L today (problem was there before)








Title: Re: jerking engine with AC on
Post by: terminator on September 08, 2014, 12:33:25 PM
I installed light flywheel and had the same problem as yours.
I also tried to add some torque reserve on idle and nothing changed. After that I added 100-150 RPM (dont remember exactly), and now its much better.
Also check KFZW map, if ignition angle was changed on idle it can be the reason of engine shaking)


Title: Re: jerking engine with AC on
Post by: aef on September 09, 2014, 12:23:01 AM
hmm but my sachs kit isnt light


Title: Re: jerking engine with AC on
Post by: terminator on September 09, 2014, 08:19:21 AM
But its lighter than stock? I dont use 1kg flywheel also. Mine weighs 7kg.


Title: Re: jerking engine with AC on
Post by: aef on September 09, 2014, 11:11:20 AM
Yes it is lighter, but i dont know how much.

log attached


Title: Re: jerking engine with AC on
Post by: aef on September 12, 2014, 01:50:54 AM
swapped my injectors two days ago
now i have the 0280158298 EV14 with 3bar fuel pressure.
The engine runs much softer and somehow quiete.

next step would be to change the fueling (krkte) and to set the fkkvs to all 1s.

i will report back how my dancing ignition angle will behave


Title: Re: jerking engine with AC on
Post by: aef on December 18, 2014, 06:26:15 AM
it is gone with the ev14s dialed in

one problem leads to another...
http://nefariousmotorsports.com/forum/index.php?topic=7379.0title=


Title: Re: jerking engine with AC on
Post by: dream3R on December 20, 2014, 02:10:46 AM
There's a set of maps in Volvo ME7 for AC torque reserve, I had to massage them for the DEKAS.


Title: Re: jerking engine with AC on
Post by: aef on February 27, 2015, 12:55:18 AM
shame on me: all solved with correct TVUB for my ev14's