BAG Engine Underpowered - Stuttering / Dithering / Misfire - What to log on VCDS?

Hi,

After getting the oil leak sorted on my BAG engine (turned out to have a stripped thread on one of the bolts for the timing chain cover) the car has started to stutter when driving along at between 30-50mph.

You can feel the engine almost slightly cough or misifre.....

I've not detected a misifre on VCDS using the measuring blocks.


I've also got no error codes to help with diagnose the issue.....unless it is a mechanical issue.....like the timing being ever so slightly out perhaps?

I did use all the proper tools for the timing chain job and the car was running sweet before sorting the stripped thread on the engine block for the timing chain cover.


What should I be logging on VCDS to help me find out the issue?


I was thinking I need to look at fuel pressures, RPM, EGR? But I haven't got much of an idea in fairness.


Could this issue be related to a bad low pressure fuel pump (LPFP) or high pressure fuel pump (HPFP)......cam follower / bucket was changed a while back but when doing the engine

swap it looked in good condition when I took it out. The relay for the LPFP was also replaced a year or 2 ago with a genuine VW part.


The injectors were also all ultrasonically cleaned using an ASNU machine so not suspecting a bad injector.


Perhaps its an air leak, or maybe a bad spark plug or coil pack but not getting any codes for them?


Any help would be appreciated.

To me that is running lean, I would check the lambda correction values. A quick test is to turn off the Lambda control in Basic Settings 099 and see if the hesitation clears but not for too long as it can upset the cat. By the way, according to VAG cleaning FSI injectors damages them and makes then run... lean.

Could removing the timing chain and have timing off make the engine run slightly lean?

Seems very strange as it was running perfectly well before the thread reapir....no stuttering or "lean" condition.....

Running lean can also be caused by air leaks too right? Should I be looking for something like that or not?


What MVB blocks in VCDS do I need to look at......is this what they call "fuel trims" or is lambda correction values something else?

I remember reading something about them and the value should change from +VE and -VE.....but I could getting confused here.


I am just trying to pin point what else I might have done during the thread reapair on the block that may have caused this.....

I did release the engine from its mounts and used an engine support to lower the engine to get enough access so I had line of sight with a drill.....

Just thinking whether this may have pulled on the wiring harness or something?


Ah bugger so I may ruined the injectors by cleaning them? They did seem fine after having them cleaned and didn't notice any issues....


After doing the lambda check would it be worth changing out the injectors for some other ones? (Obviously replacing the teflon seals and o rings with new ones too).


Never done the 099 basic setting.....what will happen exactly? and how long is too long? Can I drive a couple of miles, 10 miles? Just don't want to cause damage to the cat.......(the downpipe cat was

replaced with a non genuine part / aftermarket as they were far too expensive....

Fault codes scan from VCDS.....

Code:

---

Friday,13,August,2021,18:06:20:33544
VCDS -- Windows Based VAG/VAS Emulator Running on Windows 7 x64
VCDS Version: 21.3.0.0 (x64)
Data version: 20210226 DS325.0
www.Ross-Tech.com




VIN: WVWZZZ1KZ4W096975  License Plate:




Chassis Type: 1K (1K0)
Scan: 01 03 08 09 15 16 17 19 25 42 44 46 52 56


VIN: WVWZZZ1KZ4W096975  Mileage: 367880km-228590miles


00-Steering Angle Sensor -- Status: OK 0000
01-Engine -- Status: Malfunction 0010
03-ABS Brakes -- Status: OK 0000
08-Auto HVAC -- Status: Malfunction 0010
09-Cent. Elect. -- Status: Malfunction 0010
15-Airbags -- Status: OK 0000
16-Steering wheel -- Status: OK 0000
17-Instruments -- Status: OK 0000
19-CAN Gateway -- Status: OK 0000
25-Immobilizer -- Status: OK 0000
42-Door Elect, Driver -- Status: OK 0000
44-Steering Assist -- Status: OK 0000
46-Central Conv. -- Status: Malfunction 0010
52-Door Elect, Pass. -- Status: OK 0000
56-Radio -- Status: OK 0000
 
-------------------------------------------------------------------------------
Address 01: Engine        Labels: 03C-906-056-BAG.lbl
  Part No SW: 03C 906 056 BA    HW: Hardware No
  Component: MED9.5.10      G00 5697 
  Revision: 00000000    Serial number: VWZ7Z0D9331576
  Coding: 0000072
  Shop #: WSC 01279 785 00200
  VCID: 63C1C201A2D6B093BE-8036


1 Fault Found:
18729 - Oxygen (Lambda) Sensor B1 S1
            P2297 - 001 - Control Range Exceeded during Deceleration
Readiness: 0000 0000


-------------------------------------------------------------------------------
Address 03: ABS Brakes        Labels: 1K0-907-379-MK60-F.lbl
  Part No: 1K0 907 379 K
  Component: ESP FRONT MK60      0103 
  Coding: 0019073
  Shop #: WSC 01279 785 00200
  VCID: 3A7F5F6575DC915BCD-806E


No fault code found.


-------------------------------------------------------------------------------
Address 08: Auto HVAC        Labels: 1K0-820-047.lbl
  Part No: 1K0 820 047 CB
  Component: Climatic PQ35  080 0201 
  Shop #: WSC 00000 000 00000
  VCID: 66C7DB1551E4C5BB59-8032


1 Fault Found:
00229 - Refrigerant Pressure
            002 - Lower Limit Exceeded


-------------------------------------------------------------------------------
Address 09: Cent. Elect.        Labels:. 3C0-937-049-23-M.lbl
  Part No SW: 1K0 937 049 K    HW: 1K0 937 049 K*
  Component: Bordnetz-SG 1.0 H30 0701 
  Revision: 00030000    Serial number: 00000000514812
  Coding: E48D0F0600041800001400001400000000
  Shop #: WSC 00000 000 00000
  VCID: 3779465146CE8C3332-8062


  Subsystem 1 - Part No: 1K2 955 119 B  Labels: 1KX-955-119.CLB
  Component: Wischer VW350  012  0401 
  Coding: 00065493
  Shop #: WSC 00000 


  Subsystem 2 - Part No: 1K0 955 559 K  Labels: 1K0-955-559-AF.CLB
  Component: RegenLichtSens 002  0505 
  Coding: 00217125
  Shop #: WSC 00000 


1 Fault Found:
01049 - Supply Voltage Term 50
            006 - Short to Plus - Intermittent


-------------------------------------------------------------------------------
Address 15: Airbags        Labels: 1K0-909-605.lbl
  Part No SW: 1K0 909 605 A    HW: 1K0 909 605 A
  Component: 0M AIRBAG VW8  022 0500 
  Revision: 04022000    Serial number: 0033FD08P0VC 
  Coding: 0012365
  Shop #: WSC 01268 785 00200
  VCID: 2A5F6F25857C21DBBD-807E


  Subsystem 1 - Serial number: 6332MSME5D7E1002


  Subsystem 2 - Serial number: 6342MSME57340A02


  Subsystem 3 - Serial number: 6351HSME43485801


  Subsystem 4 - Serial number: 6361HSME5D0F5901


No fault code found.


-------------------------------------------------------------------------------
Address 16: Steering wheel        Labels: 1K0-953-549-MY8.lbl
  Part No SW: 1K0 953 549 A    HW: 1K0 953 549 A
  Component: Lenksäulenmodul 012 0030 
  Coding: 0000022
  Shop #: WSC 01279 785 00200
  VCID: 306B7D4DA3A05B0B73-8064


No fault code found.


-------------------------------------------------------------------------------
Address 17: Instruments        Labels: 1K0-920-xxx-17.lbl
  Part No: 1K0 920 950 K
  Component: KOMBIINSTRUMENT VDD 3554 
  Coding: 0000401
  Shop #: WSC 00218 210 03908
  VCID: 306B7D4DA3A05B0B73-8064


No fault code found.


-------------------------------------------------------------------------------
Address 19: CAN Gateway        Labels:. 1K0-907-530-V1.clb
  Part No SW: 1K0 907 530 C    HW: 1K0 907 951
  Component: Gateway        H08 0080 
  Revision: 08          Serial number: 2100104128EF35
  Coding: 3D0F0340070003
  Shop #: WSC 01279 785 00200
  VCID: 27599611966E1CB3A2-8072


No fault code found.


-------------------------------------------------------------------------------
Address 25: Immobilizer        Labels: 1K0-920-xxx-25.clb
  Part No: 1K0 920 950 K
  Component: IMMO                3554 
  Shop #: WSC 00000 000 00000
  VCID: 306B7D4DA3A05B0B73-8064


No fault code found.


-------------------------------------------------------------------------------
Address 42: Door Elect, Driver        Labels: 1K0-959-701-MIN1.lbl
  Part No: 1K0 959 701 E
  Component: Tuersteuergeraet 09 0116 
  Coding: 0000052
  Shop #: WSC 01279 785 00200
  VCID: 306B7D4DA3A05B0B73-8064


No fault code found.


-------------------------------------------------------------------------------
Address 44: Steering Assist        Labels: 1Kx-909-144-G2V1.clb
  Part No: 1K2 909 144 E
  Component: EPS_ZFLS Kl.1      1202 
  Shop #: WSC 00000 000 00000
  VCID: 2E576335B9944DFB61-807A


No fault code found.


-------------------------------------------------------------------------------
Address 46: Central Conv.        Labels:. 1K0-959-433-MIN.clb
  Part No: 1K0 959 433 BL
  Component: 01 KSG              0301 
  Coding: 81E802087F2D8505485BC61000
  Shop #: WSC 00218 210 08203
  VCID: 7BF19A613A66685396-802E


  Subsystem 1 - Part No: 1K0 951 605 C
  Component: LIN BACKUP HORN H05 1501


  Subsystem 2 - Part No: 1K0 907 719
  Component: Neigungssensor  003 0003


  Subsystem 3 - Part No: 1K0 951 177
  Component: Innenraumueberw.004 0101


1 Fault Found:
01134 - Alarm Horn (H12)
            004 - No Signal/Communication


-------------------------------------------------------------------------------
Address 52: Door Elect, Pass.        Labels: 1K0-959-702-MIN1.lbl
  Part No: 1K0 959 702 E
  Component: Tuersteuergeraet 09 0116 
  Coding: 0000052
  Shop #: WSC 01279 785 00200
  VCID: 316D7849A8AA52037C-8064


No fault code found.


-------------------------------------------------------------------------------
Address 56: Radio        Labels: 1K0-035-1xx-56.lbl
  Part No: 1K0 035 186 J
  Component: Radio BNO          0016 
  Coding: 0040400
  Shop #: WSC 01279 785 00200
  VCID: 2D556439B49236E358-8078


No fault code found.


End-------------------------(Elapsed Time: 01:36)--------------------------

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Do a learnt values clear in Adaptation do this three times. Then go into Basic Settings 04 and do a throttle body set and then an EGR set, take the car for a run and do an overrun EGR test, check the Readiness code shows the EGR is OK. Also do a manifold adaption but I suspect you have a small air leak.

Thanks Crasher appreciate the help.

how do I perform each of these operations?


learnt clear values clear adaptations - three times?

throttle body reset (this is in basic settings from memory in engine module?)

egr set (engine module basic settings?)


not heard of an egr overrun test??

manufold adaptation too not sure if this is in basic settings on Engine module?

how is readiness checked? In MVB?


if you can provide instructions that would be greatly appreciated.


how do I identify a trace the air leak? Where could that be coming from? Intake or exhaust side? Do I need to do a smoke test or spray with brake cleaner and listen to exhaust nite?



i did perform an egr adaptation and throttle body adapatation yesterday but think car is still spluttering?


they only thing I can think of is that I’ve used a different manifold to cat exhaust stud as it sheared off when removing the Downpipe. Perhaps there is a leak before the oxygen sensor (bank 1 sensor 1).

Was also thinking that potentially the change from E5 to E10 might be having a influence here too? But don’t think this is live until September? But I have seen in a few petrol stations that the labelling has changed already to E10.....could this be causing my issue?

I think my engine is impacted by this fuel change and will damage the seals on the injectors due to the higher ethanol content?

would it be worth pulling the injectors and renewing the seals? Or replacing injectors? I do have a spare set that haven’t been cleaned with ultrasonics.

With your engine being an early BAG, VAG have stated this engine is not suitable for use with E10, run it on the “protection” grade but to be honest these have always need 99RON since they were introduced… it is just that VAG UK hopped they would get away with it and roughly, they did.

No worries I shall run with the RON99 / V Power Shell and see if that makes a difference.

How do I find the small air leak?


Tried the adaptations above but still getting the stutter (no misifre detected according to VCDS though.....)

A smoke machine is the usual way if you can't hear it.

Is there any particular spots I should pay attention too regarding leaks?

is it best with the engine cover off?

at idle? Or revving at a particular range?

Can you also advise about resetting learned values in engine module > adaptations........

Is this the same as doing a battery disconnect for an hour? or touching the terminals together to completely discharge?

Or completing an autoscan and clearing codes? (Hear this resets fuel trims?)

It comes up with a pop up that says something along the lines:

WARNING
Resetting adaptations in this module is likely not reversible,
and reparametrization may require
the dealer tool with an online connection.


Are you SURE you want to proceed.


Attachment 38261

Yes, that's the one. The crankcase of the engine must be air tight or the breather system will draw in air, to test the system you pressure test with a smoke machine from the throttle body and look for leaks.

Could I therefore potentially have a leak on the oil sump? if this hasn’t been sealed correctly? Would that cause the rough running?

Yes, or the chain cover but you would expect an oil leak if that were the case.

It’s all looking pretty dry under there with no obvious leaks.

Will have to get it smoke tested but I don’t have one myself. Shall have to get it booked in somewhere that has one.


So the whole or the crankcase has to be sealed otherwise you’ll get an air leak and therefore lean running?


can lean running be identified with fuel trims in vcds? There are long and short fuel trims from what I’ve seen.

Yes the crankcase as a whole must be air tight, the air in is provided by a breather line and the crankcase fumes vented out of the breather into the inlet manifold. There is a display for lambda correction, this needs to be less than ten percent, it should be labelled in advanced measuring blocks. In Basic Settings 099 you can also turn the Lambda control off but that is only useful if you have a pre cat sampling port and a five gas analyser.

Lambda correction shows as 1.16

Attachment 38264

Update .....after looking at misfire counter MVB 014, 015, 016

I am getting misfire on cylinder 1 (ocassionally) but mainly cylinder 2....

Just doing the test in netural on the driveway but the misfire recognition keeps going from enabled to disabled....

Do I need to go on a drive to check and log this?

Also it seems to clear the counter to zero when I lift foot off throttle?


But looks like Ive got a misfire on cyl 1 and cyl 2....


Should I be swapping round coils and new plugs? Or just replace the lot?

Compression check would be a good idea too....

Please advise as to what to do next.

Thanks


Attachment 38265

Also keep reading about a bad earth under the passenger headlight that can impact the coils?

Is there a picture of this somewhere so I can confirm if it’s a bad earth / broken / severed cable?

Get a compression test done.

Cylinder 1 150psi 10bar
Cylinder 2 150psi 10bar
Cylinder 3 150psi 10bar
Cylinder 4 137.5/140psi 9.5bar

Good compression on number 2 with a misfire suggests plug/coil pack; they don't like being removed.

Ok thanks for the advice.

So you recommend replacing all coils and plugs?

Why does removing the coil packs damage them?



We did find an air leak / split hose on the vacuum line to the solenoid and intake manifold for the intake runner flaps....

Replaced with a new hose but hasn’t made a difference for the misfire.


The misfire did spread to other cylinders too...have detected it across all
of them now but it is quite sporadic.

What brand of coil pack should I use? OEM or BOSCH? Or something else?

is the latest revision 036 905 715 F

Personally I would fit Bosch coils and plugs, the latest number for the coils genuine is 036 905 715 H which is a Bosch 0 986 221 023 and the plugs are FGR 6 HQE 0

Yep got the Bosch coils as above (0986 221 023) but couldn’t get hold of the Bosch sparks plugs so went for NGK ZFR6S-Q