2.5 TDI: Idle Rattle (BDG 163HP) - Fix!

Hello everyone,

I'm getting gray hairs from a 2.5 TDI with a BDG engine.

The car is shaking and sputtering when idling, and it's emitting black smoke.
The dosage limit is set at -4.xx mg per injection for cylinders 1 and 4, sometimes also 6.
'When the car is started cold, it exhibits the problem. However, it doesn't occur after about 10 minutes of driving, nor does it happen when the engine speed exceeds 1600 RPM.'

'Funding start is disabled. Tested with the default setting at 2.2°N offset. AGR (Automatic Guided Rail) system deactivated using a metal plate.'

Here's what's new: LMM (mass airflow sensor), VEP (valvetronic electric pneumatic system), camshafts, pistons in cylinder 1, valves re-ground (cylinders 1-3), timing belt, oil temperature sensor on the turbocharger, throttle body, fuel filter... I can't remember any more ... Bank 2 has a completely new cylinder head.

Does anyone have any other ideas about where I could look?
Oh yeah... of course, the error memory is empty.

Are you sure that the balance shaft is in the correct position?

Hmm, the car doesn't feel like it has those wobbling movements that the machine might be causing...

Okay, well – I'll try anything – how can I check the correct alignment (VCDS? or something else?). This thing was exposed when the pistons were replaced.

Why does it work when the engine is cold, then?

Okay, I'm just thinking off the top of my head about the cooling system. If it's not working properly, you could experience symptoms like these. Try opening the oil filler cap after driving for 5 minutes; if you hear a hissing sound, then you know something is wrong.

Here's a log of what happened... today it started making a cold start noise right after starting up again.

Update: Realigned and easy to read.

Update 2... Unfortunately, it's not KGE either.

Try disconnecting the water temperature sensor.
Is the metal sheet still intact after the EGR cleaning?

Did he experience this stuttering before the work was done?
Why was one piston replaced?
Is chip tuning installed or was it in the past?
I'm not familiar with that specific Multitronik, but I know they are prone to issues . Does it only shake when idling (P), or also when in drive (D)?
Does it have full power otherwise, and can it reach its maximum speed?

Quote:

The car is idling roughly - or rather, it's misfiring... and it's emitting black smoke. The quantity limit is set to -4.xx mg/dose on cylinders 1 and 4, sometimes also 6.

Hello,

I would like to remove and verschandeln the nozzle holder combinations again.
At the same time, you can also perform a compression test on all cylinders.

Black smoke indicates either too much fuel (injectors?) or not enough air (valve actuation, foreign objects in the intake manifold).

Best regards, Rainer.

Were the hydraulics also replaced?

Okay, I guess I have to elaborate further...

The car had these problems before. It was then taken to a workshop. There, the cylinder head was removed, and a new water pump and timing belt were installed. Unfortunately, they did a shoddy job and misaligned the belt... The result is shown in the pictures... Cylinder 6 has total damage... The rocker arm is broken, etc.

'Both cylinder heads were completely overhauled (including all components like the rocker arms, all from Audi). After the overhaul, the engine still had the same problem as before. Cylinder 1 was not showing any compression. When removing the piston, it came out extremely hard, so a new one was installed... The valves were re-ground again... but nothing changed.'

We only recently decommissioned the AGR (Advanced Gas-cooled Reactor) – we also renewed the VEP (Voltage and Electrical Power) system, but there's been no improvement.
The vehicle reaches its maximum speed and runs smoothly above 1600 RPM.
No chip tuning.

The fuel injectors for cylinders 1 and 2 have been refurbished by Bosch.

Okay, even without being a motor expert, if a workshop had messed something like this up on my engine, I would have insisted on replacing the entire engine. Where that valve was damaged, there's likely more wrong than just the piston and the mark on the cylinder head. I fear this will be an ongoing problem... especially since cylinder 1 is also stuck (or was stuck). Why is that?

We'll leave the dispute with the workshop to the owner; I have documented everything.

It would be important for it to actually work.
I'm going to take the valve cover off again today and measure the compression one more time.

And here's the solution to the problem...

Cylinder 1 was sometimes showing compression, and sometimes not. I got suspicious and checked the overhauled camshafts, and then I accidentally saw this (see picture).

'Ask me how that ring could have gotten stuck like that... The fact is, this ring opened the valves a bit and then got stuck - the shaft continued to rotate inside, which is why there's no compression. However, it works at higher RPMs. Today I'm putting in a new camshaft and hopefully that will fix it.'

That's something you don't get with the 2.5-liter V6 engine.
If nothing else is broken, you're lucky. In the past, the NW would wear out, and these nowadays tightly packed things don't last either. Great thing .

It would be good to hope that the other three waves don't experience the same thing...