2.0 FSI Poor idle when cold

[drbluetongue]

Hi drbluetongue, first of all thank you for joining and replying. Nowadays it is really rare to see someone share his knowledge. People on this forum proved to be an exception

As for high idle after cold startup, i confirmed the ECU switches to different mode (010000001). In my case, engine misfires like hell on 1st cylinder (~80 misfires) and few mis on second cyl but only in warm months. In winter it is clean high idle without misfires, strange ha? After that it stays in homogeneous mode (000000001) during entire drive.
edit: today i started car in 10°C and high idle was without single misfire, mode was 000000001 entire time. So it is definitely temperature dependent.
x?xxxxxx variant is not mentioned in VCDS label but it should be some form of double injection for rapid catalyst heating as you mentioned (maybe homogeneous split? Stratified CAT heating should be ?xxxxxxx).

Switching map in runtime perfectly supports my observation. I suspected either carbon buildup or ECU playing some game with me. Generally worse acceleration (airflow) after warm up but not always. 4 bad accelerations 2 good even from low RPMs and so on. ECU compensating for something making much more sense.

I've already logged couple of hour test drive for knocks and it knocks only during high idle startup. Even idle after warmup is perfect with 0,8l/h (PCV is OK i guess).

Which MVB are you talking about when you mention
- ignition, timing angle [ °BTDC ]
- timing retardation, cylinder 1-4 [ °KW ]
- camshaft adjustment, intake B1 [ °KW ]
- phase position, bank 1 intake
- injection timing [ ms ]

I am very eager to "fool" NOX subsystem but preferably after solving this damned hesitation.

Thanks

I am meaning this:

timing retardation, cylinder 1-4 [ °KW ]

There's a separate cam timing if you get knock.

>I've already logged couple of hour test drive for knocks and it knocks only during high idle startup. Even idle after warmup is perfect with 0,8l/h (PCV is OK i guess).

Do you get any timing retardation when full throttle in say 4th gear?

[drbluetongue]

>In my case, engine misfires like hell on 1st cylinder (~80 misfires) and few mis on second cyl but only in warm months. In winter it is clean high idle without misfires, strange ha? After that it stays in homogeneous mode (000000001) during entire drive.

Yes, the catalyst heating function only works above a certain ambient temperature - how cold does it get there for you in winter?

I have a copy of the MED9.5.10 2.0 FSI FR I can give you, check the BBKH section for more information on how it works.

Do you have any access to tools to dump your ECU? (Kess, Ktag, MPPS)?

[maro]

Do you get any timing retardation when full throttle in say 4th gear?

Definitely. There is no need to push it hard for retardation to happen (especially when engine gets hot).
I read somewhere that 9KW is maximum that can be pulled.



I logged cam adjustment earlier. Unfortunately without cylinder retardation, but ECU is obviously retarding cam timing when WOT.



Here are knock voltages. They are hearing some noise for sure.

how cold does it get there for you in winter

Mild central European winter. Average of -5 Celsius.

I have a copy of the MED9.5.10 2.0 FSI FR I can give you, check the BBKH section for more information on how it works.

I have FR SG-MED9-510, VW Golf 2.0l FSI EA113 from 31.JAN.2003.
BBKH is there - Katalysator Heizen. Thanks for pointing out.

Do you have any access to tools to dump your ECU? (Kess, Ktag, MPPS)?

Yes, i ordered Chinese MPPSv16 long time ago but i was not able to read flash from ECU.
It reads ID just OK but after attempt to read flash it instantly failed (BTW their logs are scrambled).



Internet suggested to use newer version of app but i could not find it anywhere, only the version that came on CD.

I was unable to confirm that kess would work with MED9.5.1. Ktag would probably work but ECU needs to be popped open to do BDM and i would not rather do that.

[drbluetongue]

Definitely. There is no need to push it hard for retardation to happen (especially when engine gets hot).
I read somewhere that 9KW is maximum that can be pulled.



I logged cam adjustment earlier. Unfortunately without cylinder retardation, but ECU is obviously retarding cam timing when WOT.



Here are knock voltages. They are hearing some noise for sure.




Mild central European winter. Average of -5 Celsius.


I have FR SG-MED9-510, VW Golf 2.0l FSI EA113 from 31.JAN.2003.
BBKH is there - Katalysator Heizen. Thanks for pointing out.


Yes, i ordered Chinese MPPSv16 long time ago but i was not able to read flash from ECU.
It reads ID just OK but after attempt to read flash it instantly failed (BTW their logs are scrambled).



Internet suggested to use newer version of app but i could not find it anywhere, only the version that came on CD.

I was unable to confirm that kess would work with MED9.5.1. Ktag would probably work but ECU needs to be popped open to do BDM and i would not rather do that.

What version of Windows are you using with MPPS v16? I have a working software for it that works well on Windows 7/XP if you PM me.

I can confirm Kessv2 works perfectly too, in fact on my MED9.5.10 it writes in about 16 minutes vs the 38 minutes the MPPS v16 does. However both work pretty well on this setup for me

I managed to get my 1.6 FSI to 97kw (130whp) on my dyno through decat, intake, cam timing changes and making it run a LOT richer than VW did from factory, and putting more timing in. My stock tune would do what yours was doing and pull a load of timing, now I just get timing pull at low RPM but nothing I can do can help that with this high-compression engine.

[drbluetongue]

It is strange, because it does not always hesitate. After cold start or 15 minutes rest after long run it is very responsive. Response gets worse when engine gets to the operating temperature. Fuel supply and HPFP is OK - 110 Bar immediately in rail whenever throttle is pressed. I can tell based on measuring block 39/1 intake air mass when it is going to hesitate (value slooowly raising to ~40g/s) and when it shreds road (value almost instantly jumps to ~60g/s).
Response noticeably improved after cleaning throttle body and fixing that vacuum leak but it is still under my expectations.

I even make test trip with O2 sensors (B1S1, B2S1), MAP, EGR valve, IAT, camshaft adjustment valve unplugged but engine behavior was the same Funny thing the intake air mass block still showed values. There is no MAF on BLX so it is computed somehow. I tried to find out from funktionsrahmen but the german is killing me.

I am planning to order cheap compression tester from aliexpress with O2 sensor plug to do backpressure testing. After all BLX has 4 cats in my case with 220 thousands kilometers on them so they may be collapsed or melted. But i hope it's all the gunk in the intake manifold on tumble flaps and valves that is causing this.

NOX issue is currently not resolved. OEM part is absurdly expensive and i could not find spare part. Just a little warning, do not ever buy NOX sensor from China. The thing does not work right away (broken heater element) or just pretends to work but gives data that are way too off what ECU expects. I am currently trying something like software emulator for NOX. BMW guys have NOXeM but no luck for Skodas. It has its own sub ECU and communicates with engine ECU via CAN bus so it can be tapped into.

Actually i thought that stratified mode is enabled only on European cars where fuel is low on sulfur. NOX cats after primary cats and NOX sensor are sign that car is equipped with true fuel stratified injection. Have your daughter's Golf achieved stratified mode?

When you unplugged all of the sensors and tested, did you also unplug the intake flap actuator?

[maro]

When you unplugged all of the sensors and tested, did you also unplug the intake flap actuator?

Oh no, flap motor with connector is buried deep below intake manifold. It is not easily accessible area.

Finding 1
Last weekend i unplugged cam adjustment solenoid (N205). It was funny to watch that commanded cam angle was fluctuating but actual was floating around +30 crank angle which should be mechanical lock to the most retarded position.
However car's behaviour persisted - high torque from cold engine to hesitation when hot. Maybe the knock control was enforced with intake flaps or base ignition timing??

Finding 2
Full tank of higher octane fuel 95->98 worked like a magic. Throttle response improved a lot. I have never seen such improvement even with 100 octane fuel taken from other petrol station. The change was literally instant within 1 tank and ~ 300 km driven. Cam adjustment during WOT stayed on -2,5. I learned on 95 octane that it dropped to -11 when there was going to be throttle lag. I guess intake valves stayed open awhile during compression stroke, deliberately ruining compression in cylinder = reducing power = protecting A/F mix from pre ignition?!

What version of Windows are you using with MPPS v16? I have a working software for it that works well on Windows 7/XP if you PM me.

It was WXP in VirtualBox and W10. App was loaded through ugly loader. I read that version without loader should work better. I will PM you.

I can confirm Kessv2 works perfectly too, in fact on my MED9.5.10 it writes in about 16 minutes vs the 38 minutes the MPPS v16 does. However both work pretty well on this setup for me


I managed to get my 1.6 FSI to 97kw (130whp) on my dyno through decat, intake, cam timing changes and making it run a LOT richer than VW did from factory, and putting more timing in. My stock tune would do what yours was doing and pull a load of timing, now I just get timing pull at low RPM but nothing I can do can help that with this high-compression engine.

That are some great news to hear. Needless to say i am shi**ing my pants when it comes to Chinese flash tool touching my ECU. I suppose we are not talking about genuine products.

[drbluetongue]

>I guess intake valves stayed open awhile during compression stroke, deliberately ruining compression in cylinder = reducing power = protecting A/F mix from pre ignition?!


Bingo

>However car's behaviour persisted - high torque from cold engine to hesitation when hot. Maybe the knock control was enforced with intake flaps or base ignition timing??

The intake flaps stay closed until the engine coolant hits a set temperature - mine was set to 75C. Check the LBKSOL section of the FR for details on how it works, particularly FMILBNMKR:

Flaps switching based on torque when cold (Moment zur Umschaltung der LBK Abh¨angig von Drehzahl bei kalter Motor)

On the 2.0 FSI, is the position sensor for the flaps buried as well?

[maro]

On the 2.0 FSI, is the position sensor for the flaps buried as well?

I peeked into workshop manual for 1.6 85kW FSI. Your upper & lower intake manifold has different shape. Also the flaps are actuated by vacuum and dreaded plastic rod which loves to break. Feedback is done via potentiometer that is mechanically attached to the flaps shaft.

2.0 FSI has adjustable manifold length runners, which is actuated by vacuum + solenoid + vacuum controller with plastic rod and switching drum (23) inserted into manifold. This all should enhance torque above 5000rpms or so.



Intake flaps are fully operated by electric motor (no vacuum) attached to the lower intake manifold (or fuel distributor as it is called in manual). I presume position sensor is part of motor body.


Connector is on the body of motor all buried down below intake manifold.



However i tested the flaps via VCDS output test and i could hear motor buzzing as it engaged the flaps.
When i logged open angle of flaps they seemed to be actuated from cold start. I can post proper graph with temp & angle & pedal position.

[maro]

As for performance issue, right now 98 octane seems to influence car's behavior to the point i am satisfied with it. I want to drive it more in order to confirm long term behavior.

Could you please elaborate more about solving NOX sensor issues?

I can imagine a few approaches
- modifying ECU's flash to mask DTC set by sensor (heater, signal range, NOX catalyst efficiency, ...). Would not there still be issue on emission test?
- modifying ECU's flash to "code out" NOX subsystem. Homogeneous mode would be primary mode then and all benefits of stratification would be gone but no check engine light no failed emission test.
- tapping into MED ECU and NOX ECU with some arduino simulating CAN communication so MED ECU would be fooled and turned on stratified mode
- buying some emulator like NOXem for BMWs, which is basically Bosch wideband O2 sensor with its own ECU, NoX concentrations are "computed", NoX cats are useless and can be removed, i could not find any emulators for Skodas )-:
- ?

[drbluetongue]

As for performance issue, right now 98 octane seems to influence car's behavior to the point i am satisfied with it. I want to drive it more in order to confirm long term behavior.

Could you please elaborate more about solving NOX sensor issues?

I can imagine a few approaches
- modifying ECU's flash to mask DTC set by sensor (heater, signal range, NOX catalyst efficiency, ...). Would not there still be issue on emission test?
- modifying ECU's flash to "code out" NOX subsystem. Homogeneous mode would be primary mode then and all benefits of stratification would be gone but no check engine light no failed emission test.
- tapping into MED ECU and NOX ECU with some arduino simulating CAN communication so MED ECU would be fooled and turned on stratified mode
- buying some emulator like NOXem for BMWs, which is basically Bosch wideband O2 sensor with its own ECU, NoX concentrations are "computed", NoX cats are useless and can be removed, i could not find any emulators for Skodas )-:
- ?

Do you get stratified mode when you cruise along at part throttle, if you log your AFRs? Or just at idle?