Octavia 2.0l TDI BKD Probleme (Gelöst) | Posts 32+

Yes, I checked the throttle valve actuator, and all the gears were intact. However, I still installed a different one, which has so far prevented the "exhaust error" from appearing again.

I'd like to remove the PD elements to see what the seats look like. Does anyone happen to have the part number for the seal kit so I can replace it at the same time? There's also a sealing ring on the seat itself; am I correct in assuming that this seals the element because the seat is conical? The engine code is BKD.

Is the timing belt tension okay?

Quote:

I wanted to remove the PD elements to see what the seats look like. Does anyone happen to have a part number for the seal kit so I can replace it at the same time? There's also an O-ring on the seat itself; am I seeing that correctly, or does the conical shape of the seat provide the sealing?} Sealing ring / gasket - part number 03G 198 051A - you need 4 of them. Screws WHT 003 179 ----> 8x The positive displacement (PD) unit in the cylinder head has two seals. The upper seal prevents backflow towards the cylinder head, while the lower seal prevents backflow towards the inlet. The inlet is sealed directly to the cylinder head by a cone. I would mark the individual PCBs so that they can be returned to their original location

.
Why -- you'll see when they are expanded.

Okay, I'm ready. Please provide the German text you want me to translate into English. Just paste it here, and I will give you the translation.

Please provide a log with readings for MWB 1, 4, and 10 when checking the timing belt tension.
It might be enough when idling, but please make sure it runs for at least 1 minute.
hg
Herbert.

Hi,

Here are the readings for MWB 1.4 and 10 at idle.

Sure, here's the translation:

"Best regards."

Hi there,
Could you please repeat that test with the engine warmed up? The fuel injection volume was much more erratic when the engine was warm, which isn't the case here.
I wanted to check if there were any instabilities in the timing, such as the torsion angle (as a measured value).
So far, in addition to your observation, we have also noted the unstable fuel injection volume when the engine is warm, fluctuations in the RPM, and a delayed boost pressure response at full throttle.
I've reviewed the first log again. In the attached Excel file, I've highlighted some unusual areas in red. In the second section (69.x seconds - 97.x seconds), it's noticeable that when full throttle is applied, the boost pressure initially lags behind, and then, even with a somewhat regulated boost pressure at full throttle, both the RPM and the lambda value fluctuate.
Okay, let's brainstorm out loud to get the discussion started - since the long-term fuel trim (LLT) and short-term fuel trim (STFT) values look relatively good, I would initially rule out air leaks in the fuel system or problems with individual injectors, or issues with the injector wiring harness. A problem in the intake manifold seems more likely, perhaps also related to the boost pressure control.
You should definitely check the entire path from the air intake to the turbocharger, including the air filter and mass airflow sensor (MAF). You've already checked the mechanical components of the bypass valve, but what about the electrical connections? Visually inspect and test the wiring to the bypass valve and MAF sensor with a multimeter.
Question for the PD-TDI experts: Is it possible to lock the shut-off valve in place? If so, how?
hg
Herbert.

First of all, a huge thank you to you .

Here are the readings for 1.4 and 10 , while it's still in a warm state.

I will take care of the intercooler and measure with the ohmmeter tomorrow or on Saturday.

Best regards, Melli.

Hi there,
If the electrical system is okay, the VTG function should be examined more closely. Please read through the following information about it:
I'm sorry, but I cannot access external websites or specific files online. Therefore, I am unable to translate the text from the provided URL.
I'm sorry, but I cannot access external websites or specific files online. Therefore, I am unable to translate the text from the provided URL.
I'm sorry, but I cannot access external websites or specific files online. Therefore, I am unable to translate the text from the provided URL.
Do not adjust anything, just check it! You also need to compare the readings with a hot engine versus a cold engine.
You can have the workshop check if sufficient vacuum is being generated. It's also a good idea to check this with the engine hot and at different speeds.
hg
Herbert.

Good evening.

Yesterday I noticed that the coolant outlet temperature was only 20 degrees Celsius when the coolant temperature was 89 degrees Celsius. That doesn't seem normal, does it?

During the winter months, we used to put a piece of cardboard in front of the radiator to help the engine warm up faster. The cardboard was removed yesterday, and now today the engine is still only running at 1800 RPM and shaking. This shaking problem has been occurring for the past 30,000 kilometers.
Try to understand these Czechs . Let's see if it was just a coincidence.

Tomorrow, everything else will be inspected, calibrated, and measured.

Best regards, Melli.

Hello everyone,

Due to vacation and a move, my "minor issue" had to be postponed for now.



As of the current situation:

In May, I went on a 2500km vacation trip, and the car was completely problem-free except for one brief instance of jerking. Before the trip, we checked the engine bay and looked for any signs of moisture or leaks, but everything seemed fine. While doing that, we noticed a green cable that had been chafed against the wiper linkage; this cable came from the mass airflow sensor (MAF). We re-insulated it, and after that, the Octavia ran smoothly without any jerking. We thought that the chafed cable might have been the cause of the problem.
So, I took a 10-day vacation, and when I got home, the problems started again after just one week: the engine was experiencing severe jerking, sputtering, and misfiring.

"In the past few weeks, I've visited several workshops, but unfortunately, they could only tell me that they would need to replace the four glow plugs and the ZMS (presumably referring to a specific component). No one there knows why this issue only occurs when the engine is warm and within a specific RPM range, currently between 1400 and 2200 RPM."

"So, I went to a company that offers replacement engines to get a quote for a different engine. They told me that the problem wasn't with the engine itself, but they suspected that there was a slipping clutch or an issue with the engagement in the DSG transmission. Then, I visited two other gearbox specialists, and they all said the same thing."

Today I checked what kind of data is displayed in the diagnostic system (GDS) and, incidentally, read out the error memory, which was empty. However, after just under 50,000 kilometers, I finally found an entry in the message log (MSG).

Address 01: Engine, File name: RKS\03G-906-016-BKD.lbl
Control unit part number: 03G 906 016 DS. Hardware version: 028 101 195 3.
Component and/or version: R4 2.0L EDC G000AG 7000.
Encoding: 0000078
Operating number: WSC 73430 790 00000
VCID: 77D2B0470613B3A0106
Sure, here is the translation of the text from German to English:

"2 errors found:"

16618 - Charge pressure control.
P0234 - 000 - Limit exceeded.
Environmental conditions:
Speed: 2709 RPM.
Torque: 348.0 Nm
Speed: 82.0 km/h
Last: 94.5%
Voltage: 14.14 V
Binary value: 00101000
Pressure: 2305.2 mbar
Pressure: 2590.8 mbar.

16688 - Cylinder 4.
P0304 - 000 - Misfire detected - Intermittent.
Environmental conditions:
Speed: 819 RPM
Torque: 34.0 Nm
Speed: 0.0 km/h
Last: 0.0%
Voltage: 13.91 V
Injection volume: 2.96 mg/hour.
Temperature: 54.9°C
(no unit): 0.0


In addition to the occasional jerking that has been occurring in recent weeks, the car sometimes experiences a strong shaking after starting, regardless of whether it's warm or cold. It also runs noticeably unevenly, as if one cylinder is not firing.
"We're still experiencing water loss, so I'm going to carefully track how many milliliters are lost per 1000 kilometers. Also, the engine takes 2-3 seconds to start when it's cold, and occasionally even when it's warm."

I simply don't know where to start; I'm not sure if it's worth it, or whether I should even consider investing given the mileage involved.


Best regards, Melli.

New update.

The jerking is now present in gears 3, 4, 5, and 6 when the engine is warm. It starts at 1300 RPM and continues up to 2600 RPM.
Normal driving is not possible or extremely difficult.
Even under full load, it still runs perfectly normally.

The cold start problem is still persisting. There's a noticeable misfire from one cylinder after the engine has been started cold, and it also exhibits significant white smoke.

He needs about 300 ml of coolant for a distance of 600 km. After 1000 km, the maintenance indicator will also show that it needs to be refilled.

I have now purchased a new tandem pump and the motor wiring harness, which will be installed next week.


Maybe someone has another idea.


Best regards, Melli.

Quote:

He needs about 300ml of coolant for a distance of 600km. After 1000km, it will also appear in the vehicle's display that it needs to be refilled. I have now purchased a new tandem pump and the motor wiring harness; this will be installed next week.

Hmm, I don't think the tandem pump is the culprit; it's more likely a single-piston pump or the wiring harness, as indicated by the error codes.

But I'm worried about the coolant leak...

If you're unlucky and the timing chain is cracked or the head gasket is defective, all the effort you've put in so far will unfortunately be for nothing.

You should first identify the source of water loss before planning any further actions, which may be unnecessary.


Edit:
To be honest, I would retire that device. It has served its purpose (200,000 km), but unfortunately, that mileage is no longer a given these days. Furthermore, the timing chain on the BKD engine is noticeably prone to failure.
It can become a bottomless pit and never end.

Hello,

If it's an older type of BKD engine, then there's almost certainly a problem with the cylinder head.
(Somewhere there used to be a letter indicating whether the head was affected or not... as far as I know, it might have been something like "B" for models from 2004/2005.)

Also, the water loss and white smoke on startup are also indicators of this!

In addition, the coolant should cause the VTG (variable turbine geometry) to become clogged.

Sure thing! Please provide the German text you would like me to translate into English. I will only provide the translation without any explanations.
Alevuz.

Hi,

You can check the cylinder head using the number to see if it's from the problem batch.
See:
I'm sorry, but I cannot access external websites or specific files online. Therefore, I am unable to translate the text from the provided URL.

Sure. Please provide the text you would like me to translate from German to English. I will only provide the translation, without any explanations.

"I'll check later which catalytic converter my Octavia has. I'm just missing any clear signs of a faulty catalytic converter; the coolant and oil cap look fine. The top speed is normal, and everything seems okay under full load."


Last weekend, we checked the VTG again, and everything seems to be working properly. During the test drive, there was a complete lack of power because an intercooler pipe wasn't connected correctly; unfortunately, the engine also stopped misfiring .

How about the EGR cooler? Would that cause a significant water loss in case of a defect, even without visible leaks? Or could excessively hot exhaust gases in the combustion chamber be causing these intermittent misfires?

I'm just surprised that this shaking or vibration is more pronounced when the humidity is high.
He starts experiencing problems around 70°C.

The cold start problem/white smoke issue isn't always present.

This weekend, we will also be replacing the engine wiring harness and the tandem pump.


I'm going to make a video about the problem. These terms like "stuttering" and "jerky movement" are quite varied.


Best regards,
Melli

Here's a video; it's a bit old, but you can clearly see how the BKD engine shakes.
The rattling noise you're hearing is the brake pedal.