Black Smoke After Cold Start: Causes & Fixes

Once again, I'm having a problem with my ARL.

- Immediately after a cold start, it smokes black/blue.
No error codes are present in the memory.

I once tested MWB13u 23.
What do you think about it?
I replaced the timing belt with new water pump 40,000 km ago, and it still has some life left in it.
Should I act on that now?

What are your experiences with the MWB (presumably referring to a specific organization or product)?

This morning, right after the cold start, I got readings of 13 and 23 again.
I checked and found that the fourth cylinder was oscillating around approximately +3.XX.

As the engine warms up slowly, the value also decreases.

When I installed the ZK back then, I didn't adjust the PD elements.
Would you consider an audit to be worthwhile?

Could it be conceivable that the component is already defective after only 40,000 km?

I've gained new insights now.

I swapped all the elements of each cylinder and installed new seals everywhere.
I also performed the mechanical adjustments.

Unfortunately, the error doesn't follow along.
No damage is visible at the location of the PDe.

Maybe someone here has a tip on how I can proceed.
I really need your help right now.

Thank you.

'How many kilometers are on the engine in total?'

Does the blue smoke only appear after a cold start? Is the engine okay?

I'll keep it short because this is the tenth time I'm trying to formulate an answer, and that good piece of equipment (my PC ) is preventing me from doing so.

Compression is okay, maximum approximately 35 bar, with a difference of no more than approximately 0.5 bar when cold.

Cooling system bleed valve okay. (Replaced the cylinder head cover from the auxiliary water pump), but the error persists.

However, something concerns me when I consider the MWB 13.
Cylinders 1-3 are barely oscillating.
Cylinder 4, on the other hand, is consistently showing values between 0.20 and 2.30 above the normal range, and this is happening at seemingly random intervals. Why is that?

I think I have the same problem. What could it be?
I was able to rule out Parkinson's disease from the beginning.

Hi,

Quote:

Cylinder 4, on the other hand, is firing between 0.20 and 2.30 above what it should be, and it's doing so almost constantly at undefined intervals. Why??

- Wiring defect.
- Loose PD element.
- Seal of the PD element is defective.
- Defective PD element.

Best regards, Rainer.

Then all that's left for me now is actually just the wiring harness.

'I had all the components outside, new seals are in place everywhere, and there wasn't really anything visible on the seat inside the head.'
If it were the element, the error would have been included.

I'll try installing a wiring harness tomorrow and will report back again.

You also have high positive deviations in the case of defects in the mechanics, such as a leaky valve or a cracked piston. The other cylinders then have high negative values to compensate. However, since you've already measured compression, and it only occurs when the engine is cold, and the injectors have been ruled out by swapping them, my suspicion also falls on the wiring harness.

The connector on the PDE should only be removable with pliers or, after thorough degreasing, with considerable force using your fingers. If it comes off easily, then the contacts have likely become loose due to vibration, and a faulty connection has resulted.

Translation:

Review:
Have someone hold a multimeter (in resistance mode) on the central connector, touching the pin corresponding to the cylinder in question. While they're holding it, wiggle the connector. If the resistance fluctuates significantly, you've found the problem.

It's not the wiring harness.

I removed the wiring harness from my donor vehicle (ASZ) and reinstalled it, only to find out again that it probably wasn't the problem.

I also disabled the glow plug system once, just to see how it would behave. In doing so, everything got much worse, and at the current temperatures (around 10 degrees Celsius), it started misfiring badly.
I still think it must be a problem related to the fuel supply or flow.

'The friendly person doesn't want to swap heads with me, though! I actually have parts from a GW [presumably Games Workshop] model.'


Regarding my original problem:
Cold condition; Cylinder 4 MWB 13 value +2.99; Cylinders 1/2/3 have negative values of approximately -1.50.
If the cooling water temperature increases, the values will be somewhat mitigated.

g1om wrote:

I also deactivated the preheating system once, just to see how it would behave; in that case, everything gets much worse, and at the current temperatures (around 10 degrees), it starts misfiring badly. I still think it must be a problem

in the head. Fuel supply/flow . Hmm, immediately after a cold start, an injector (PDE) cannot be supplied with excessively hot diesel (= distributor pipe problem) .
If air were to accumulate in the diesel lines, it would be purged during engine operation. Replace the return hose to the fuel injection pump with a transparent piece of tubing and check if bubbles appear immediately after a cold start }.

It's not that easy to find a suitable line, and then it also needs to be transparent .

I managed to do it, but unfortunately, there's no air getting in. There's just a tiny bubble at the very beginning, smaller than the tip of a rice grain, and then nothing happens after that.
I re-measured the compression just to be sure, but the result is the same as last time. Briefly.

Cylinder 1: 29.4 bar.
2 29.8 bar
3 29.6 bar
4 29.9 bar

Would additional log files help with a better analysis?


I'm actually not in the mood to take so many exams anymore, because I still have a warranty on the cylinder head, but my dealer won't replace it! He always wants to inspect things and do this and that, and he won't get it replaced, etc.
To be honest, none of this is my problem because I'm a customer and I have a 2-year warranty on the device.

Quote:

Actually, I don't feel like taking so many exams anymore because I still have a warranty on the cylinder head, but my dealer won't replace it!

He always wants to check things and this and that, and he won't get it replaced, etc.
Honestly, none of this is my problem because I am a customer and have been with the company for 2 years.

Then it's time for you to threaten legal action. After all, you paid for it, and you have the right to a warranty.

Even if it's not entirely true, but if you tell him something about a lawyer and legal insurance, and maybe even set an ultimatum (in writing), he will definitely be more motivated. For example, I often use "more direct" methods with suppliers, and that almost always works }.

Then it's time for you to threaten legal action. After all, you paid for it, and you have the right to a warranty.

I completely agree with you.
Yesterday, I called Seat Germany, and the woman was very helpful and immediately took note of my complaint.

She will ask my dealer why the cylinder head hasn't been replaced, as there is still a warranty claim open. I hope this allows me to proceed, especially since...
I have completed all the exams that were available to me and can provide proof of this.
What really makes me angry is the price I paid back then, which was around €3000, and the complaints about what it has become since.
'It costs ???€ less to produce this thing, which is just ridiculous.'

Maybe I can still find something else that I can check to make it even more reliable.
What else would you do?

What does the intake manifold of that cylinder look like? Have you checked to see if it's completely clogged with carbon deposits?

I just had a very pleasant conversation with another SEAT dealer.
He is ready to exchange my head for a GW .

I'll start disassembling it these days, and then we'll see how far it goes.
The cylinder intake is carboned up.

I will definitely report on how things progress.

Thank you in advance for your help.