DPF: What it is and how to clean it | Posts 32+

Okay, now let's talk about the return quantity.

Nice, but without any volume specifications, measurement duration, or speed during the measurement, it's just aesthetically pleasing.
Let me tell you what I think.
- Vehicle purchased with 90,000 km (approximately 56,000 miles), with previous engine repairs likely unknown.
- White smoke upon regeneration indicates incomplete combustion, likely due to excessive fuel injection.
- Problems with regeneration -> likely due to the old DPF, but excessive soot formation is probably also a factor;
- The oxygen sensor reports "too rich" -> indicating either insufficient air for proper combustion or an excessively high fuel injection volume.
- AGR and DPF clogged with soot -> possibly due to excessive AGR operation, or potentially a generally high soot content in the exhaust.
- Soot on the exhaust side -> The air-to-fuel ratio is incorrect, indicating a faulty injection system or poor compression.
- Significantly negative values in the zero-quantity calibration for all injectors -> worn nozzles, excessively high injection quantities (which cannot be corrected further), nozzles are dripping.
In the image, all the ESDs (Electrostatic Discharge devices) need to be replaced, and after the prolonged period of malfunction, the cylinder liners should be inspected for signs of melting.
Perhaps there was an exchange of ESDs (Electrostatic Discharge devices), and maybe someone tampered with the initial quantity matching calibration (IMA). That's why I suggested a quick check in that area.
By the way, the noise you're hearing could also be caused by a collapsed hydraulic lifter. Those are likely worn out at 270,000 km. I would check that immediately.
hg
Herbert.

Okay Herbert, the measurement was taken over 6 minutes, and that was at idle. I did give it some gas at the beginning for about a minute to get it started. I've ordered some new injectors, and they're arriving tomorrow. Tonight, I'll remove the old ones and take off the valve cover. Then I'll take a look at how the valve lifters look.

After changing the injectors, it's a little better. But only a little. It also doesn't run as rough anymore. And it starts up better again, but not like it used to.

And what have you recorded just now?
hg
Herbert.

That was a log in a stand.

Hi.

Frankbe wrote:

That was a log in the stand.

It seems to be an issue with the idle speed control. It could be a mechanical defect in the cylinder or a faulty fuel injector.

-> Perform compression test and inspect nozzles.

Best regards, Rainer.

It would be helpful if we knew what you did, and what you didn't do.

Which specific nozzles were replaced?
Were new seals installed?
Part numbers for the old nozzles?
Part numbers for the new nozzles?
Supplier and manufacturer of nozzles?
IMA values have been read and accepted by the control unit?
Were the learning parameters reset?
Was the fuel injection system bled?

And as for that:
What are the current values for the rail pressure calibration?
Are the hydraulic lifters okay?

hg
Herbert.

Okay, here's something from me again. Today, I measured the compression. The problem is that cylinder 1 and 2 both have 12 bar, while cylinder 3 has 22 bar and cylinder 4 has 23 bar. The injectors are Bosch, refurbished, and the same ones that were installed before.


Now comes the big question: what should I do? Should I sell it or repair it? If I knew for sure that it was just the head gasket, I would be willing to attempt the repair myself.

Frankbe wrote:

Okay, here's something from me again. Today, I measured the compression. The problem is that cylinder 1 and 2 both have 12 bar, cylinder 3 has 22 bar, and cylinder 4 has 23 bar. And the injectors are Bosch, refurbished, and are the same ones that were in before. Now comes the question of all questions: what should I do? Sell it or repair it? If I knew for sure that it was only the head gasket, I would dare to repair it.

Hello,

It depends on how much time you have and what resources are available to you. Somewhere in the first few posts of this thread, I read something about 274,000 km.

Only you can determine whether it's worth the effort and expense to repair the rest of the vehicle.

Generally speaking, with this mileage, you should expect further failures of all sorts of parts on a daily basis.
This not only costs money, but above all, it takes up more (working) time.

Best regards, Rainer.

Hi,
You're not explaining enough. Please address our questions.
Were the poor compression values observed in the cylinders where you had the injectors refurbished?
At first, the LLR was good, but now it's completely broken.
hg
Herbert.

I've replaced all the injectors. I also checked the hydraulic lifters. Last week, I got a cheap engine with 130,000 km, but it also has a problem, but it was a good deal. If only I knew what to do? Everything's been terrible for the last two years, and now this. I'm going on vacation on Thursday and will think about what to do there.

Which nozzles were exactly replaced? all
Were new seals installed?
Part numbers for the old nozzles?
Part numbers for the new nozzles?
Supplier and manufacturer of nozzles?
IMA - Were the values read into the control unit (STG) and accepted?
Were the learning parameters reset?
Was the fuel injection system bled?
What are the current values for the rail pressure calibration?
Are the hydraulic lifters okay? yes

2/10
"stop being so nosy"
hg
Herbert.

Everything is good and fine, and taking stock makes sense.

If the compression test was performed correctly, the hydraulic lifters are okay, and two cylinders are truly defective, I wouldn't hesitate for long.

Basically, you have the following options:
- Repairing a worn-out engine with many kilometers is expensive, and a new one won't be installed. The cylinder head needs to be removed, and if the hydraulic lifters are okay, the problem must lie with the valves, pistons, or piston rings, which would make the repair just as complex and expensive.
- Used engine with clearly documented lower mileage; some components from the old engine can potentially be reused or exchanged.
- The car is in very poor condition overall, and more repairs are needed. It's probably best to get rid of it.

Make your choice.

Neue Abdichtungen wurden eingesetzt? Yes.
Part numbers of the old nozzles? The numbers were identical.
Part numbers for the new nozzles?
Lieferant und Hersteller der Düsen ? Bosch. Dieselfix Neuss.
IMA - Values have been read and accepted by the control unit? Yes.
Learning parameters have been reset? Yes.
Fuel injection system bled? Yes.
What are the current values for the rail pressure calibration?

Ich habe die Düsen auch mal getauscht von 2 auf 3 und 1 auf 4 und die Werte alle wieder neu eingegeben und die Werte auf den 1 und 2 sind gleich geblieben. A


I'll probably sell it. I think that's the better option. Let's see what I can get for this broken thing. The front brakes need to be replaced. The rear shocks are shot. The tires are also worn out. Who knows what else might be wrong. And there are plenty of comparable, slightly newer models with fewer miles available online.

And now, since I need to look for something else, I'd like to know which engine I should avoid.

I will probably buy a diesel again. Because they are more fun . I just saw that there is a Seat Leon with 184 hp, has anyone had any experience with that?
I definitely want another 2.0-liter engine. And since the budget isn't great, it will probably be at least 3 years old and have around 150,000 kilometers (approximately 93,000 miles) on the odometer. I'm leaning more towards the Golf Variant, though.