Kaltstartproplem beim 1Z nicht gelöst *heul* | Posts 16+

haehnlein wrote:

... I certainly don't want to question the physical limits!! But I'm still surprised that my father's car manages 260,000 km without any problems (and others do too), with only two fuel filter changes and using gasoline from "independent" stations, while my meticulously maintained vehicle is completely unreliable!

For some, more; for others, less...

Why does one fuel filter clog after 50,000 km while another one lasts for 100,000 km?
It really depends on the fuel quality, and that applies to the injectors as well.

Quote:

And the natural gas engine in the 1Z is really not a masterpiece of engineering at all!

Bosch sees things a bit differently (since they are the ones who developed it).

Quote:

I just want to make sure that before I go out into the snow again and spend another 380 euros to check the injectors, there isn't something else causing the problem!

Remove the injectors and have them pressure tested at a Bosch service center... It doesn't cost much, but it provides peace of mind.

Quote:

It seems that the fuel flow was too high due to the incorrect distribution of the electronic direct control (EDC) in the third cylinder (in a single-cylinder engine), which caused the piston to melt. That's at least my understanding of what happened.

The injector needles are getting stuck.

Quote:

I called Bosch and VW again. VW: Nozzles are dripping. Bosch: At 174,000 km, it's unlikely to be a problem with the pump itself, but rather with the mechanical components within the pump, specifically the fuel injector control.

Is the Bosch service trying to sell you a new pump? $$$$$$$

Mein Boschdienst hat mir gesagt die (sinnvolle) Lebensdauer einer TDI Düse beträgt 150.000 - 200.000km! Wo liegst du jetzt?? MIttendrin!!
I replaced mine when it was just over 150,000 km, and I took one apart. The needle had a wavy surface on the sealing area.

@Ulf

The NBF, due to its complex construction, is ideally suited for providing needles (and thus also for dealing with melted pistons).
Trading NBF alone? Not with the current performance of KM.

@Albrecht

The nozzles don't necessarily need to be replaced, but I would at least have them checked to be sure.
Christian checked the heating system, and even replaced the candles (or am I mistaken, Christian?).

Hi,

I suspect the problem lies deeper within the preheating system.
My AAT is also very selective and sensitive when it comes to preheating.
If I don't preheat the engine (which is an option I can set) when the temperature is between 7-10 degrees Celsius, it still makes a lot of noise for a while, even though TDIs are supposed to be relatively easy to start in cold weather.
If I preheat the engine, it starts faster than I can even turn the key.
Also: If Christian plays the organ for a long time, doesn't diesel fuel also accumulate in the combustion chamber, which then produces a white cloud?
So it doesn't necessarily have to be caused by dripping nozzles?

Ich würde mal den oben erwähnten Tipp beherzigen, den Temperaturgeber abzuziehen. Wenn er dann super anspringt, sollte die Vorglühanlage i.O. sein, denn dabei wird min. Temperatur vorgegaukelt, d.h. max. Vorglühdauer und max. Staamount.
It's possible that this sensor is faulty and reporting an incorrect coolant temperature to the control unit, which prevents the glow plugs from activating.

Regarding the German Civil Code (Bürgerliches Gesetzbuch - BGB):
I once read in another post that a faulty automatic tensioner (NHG) can cause belt slippage, which in turn can lead to cracks in the timing belt and damage to the idler gear wheels.

Markus H. wrote:

Regarding the German Civil Code (Bürgerliches Gesetzbuch - BGB): Ich las in einem anderen Posting mal, daß ein defekter NHG durch die entstehenden Ruckler auch gern Zahnriemenrisse und ausgeschlagene Krubelwellenräder verursacht.

Hi Markus,

That was in connection with the five-cylinder engine, and the post was from me.
I'm not aware of that happening with a four-cylinder engine, but I certainly wouldn't rule it out as impossible.

Okay, please provide the German text you would like me to translate into English.

I checked the glow plugs again with a multimeter while the sensor was disconnected -> voltage is present (glow plugs are new). However, it was strange that there was a changing resistance to measure between the glow plug connection cable and the fuse box (8-30 ohms). It should be zero, shouldn't it?

At least the engine was still warm to the touch, and it only started after 5-9 seconds, followed by a short, uneven idle, plus a brief puff of diesel-smelling smoke for 5 seconds, after which everything returned to normal (which rules out a problem with the glow plug system).

@Nozzle Specialists:

I made a deal with my father: over the weekend, I will install his new nozzle set, which is only 2 weeks old.

And then maybe there will be something for the error database!

@Ulf:

I also remember the mechanic mentioning something about a stuck needle in the NFB (Negative Feedback Bus).

Best regards, Christian.

Hi!

Check this out:

http://www.euregio.net/edu/zawe/kfz/Praxis2.htm

Best regards,
Uwe

haehnlein wrote:

So: I checked the glow plugs again with the multimeter while the sensor was disconnected -> voltage is present (new glow plugs). However, it was strange that a changing resistance could be measured between the glow plug connection cable and the input fuse box (8-30 ohms). That should be zero, right?

Hi Christian,

Have you measured the voltage at a disconnected spark plug terminal? That doesn't necessarily tell you anything about the voltage that remains at the spark plug when even a tiny amount of resistance (0.01 ohms) is added.

Meaningful measurements can only be obtained with a connected and intact candle.

With the measured resistance value, I can't do anything specific right now; I need the exact terminal designations.
Specifically, digital multimeters can sometimes react to even a small amount of dirt on the contact surfaces by displaying wildly fluctuating values instead of showing 0 ohms.

After an 8-ohm resistance in the spark plug wire, very low voltages should be measurable on a healthy spark plug (in the range of approximately 1 volt).

peculiar, peculiar; strange, strange.

@Ulf:

I only measured the resistance of the wiring from the input fuse to the glow plug connection (fuse check). However, one glow plug was still connected at the time (which is an error).


I just went outside again and noticed something strange:

Mir hat es keine Ruhe gelassen mal den Motor mit abgezogenem Geber zu starten. Habe aber erst die Spannung an EINER abgezogenen Leitung beim Vorglühen gemessen (so um 12 V). Dabei hat aber der Absteller 2 Sekunden lang ganz oft geklackert!!!!! Und es war totsicher der Absteller (normalerweise ein Klack bei Zündung EIN und einer bei AUS) und nicht etwa das Magnetventil. Danach habe ich ihn 10 Sekunden vorgeglüht und siehe da der Motor war sofort an!!! Es kam zwar noch ein winziges Wölkchen raus, aber IMO normal für einen Kaltstart. So and now what?

Could it be that the dispenser is malfunctioning, or perhaps the EDC (Electronic Data Carrier) is directing it incorrectly? Is there a way to check this?

Best regards, Christian.

@Ulf:

I forgot to mention that my glow plugs are connected with a continuous wire (not individual wires). That means if I disconnect one connection, I measure the voltage drop across three glow plugs! Around 12 volts should indicate properly functioning plugs (and they are new anyway).

Best regards, Christian.

Hello Christian,

If your starter motor is clicking, I would start by investigating that first. Check the voltage at the starter motor to make sure you're not experiencing a poor connection.
A foreign object in the parking space is also conceivable.

Regarding the nozzles again. Henzo has depicted the spray pattern of a new and a used hole nozzle (similar to TDI) from a tractor. The nozzle is not defective!!! Now, you can convert 5000 hours of operation into mileage (I estimate about 100,000 km) and get an idea of the combustion process with both nozzles.

Hi Bertil,

du bist echt gemein. Ich spiele immer mehr dem Gedanken meine Düsen zu tauschen. Und dein Link trägt nicht gerade dazu bei, dass ich mir das Geld spar und weiter mit meinen Altbewährten (seit knapp 215.00km) rumzueiern.

If they weren't so expensive...
I once asked out of curiosity what it would cost me at VW (just the nozzles): €500 for replacements and €1000 for new parts, which was told to me with a slight smile.

Well, we'll see what happens; time will tell (or maybe not).

Best regards.
David.

Bertil wrote:

The NBF, due to its complex construction, is ideally suited for providing needles (and thus also for dealing with melted pistons). Can you swap the NBF alone? Not with the KM performance...

Hi Bertil.

I think you mean "needle bounce," which means the nozzle isn't closing properly.
How can something like that happen? Calculus formation, feather breakage...??

Do you have any estimates of how often something like that happens?

haehnlein wrote:

Mir hat es keine Ruhe gelassen mal den Motor mit abgezogenem Geber zu starten. Habe aber erst die Spannung an EINER abgezogenen Leitung beim Vorglühen gemessen (so um 12 V). Dabei hat aber der Absteller 2 Sekunden lang ganz oft geklackert!!!!! Und es war totsicher der Absteller (normalerweise ein Klack bei Zündung EIN und einer bei AUS) und nicht etwa das Magnetventil. Danach habe ich ihn 10 Sekunden vorgeglüht und siehe da der Motor war sofort an!!! Es kam zwar noch ein winziges Wölkchen raus, aber IMO normal für einen Kaltstart. So and now what?

Hi Christian,

If the engine starts perfectly fine during a simulated ultra-cold start, it's probably not due to the kill switch, because the kill switch doesn't care whether the sensor connector is plugged in or disconnected.
Sometimes, when the engine is cold before starting, I hear a rattling sound coming from the area of the ESP (Electronic Stability Program) on my tractor. I suspect it's the RWG (Rollover Mitigation System) check routine, where the pump opens and closes several times.

Right now, I suspect there might be a problem with the temperature sensor. Use VAGCOM to check the values of all three sensors in group 7 while the engine is cold.
I can easily imagine that the coolant temperature sensor is showing a significantly higher reading than it should.

Addendum:

You just never know what you're going to find.
The combination sensor for the Electronic Control Unit (ECU) and instrument panel has two sensing elements with different resistances. The one used for display purposes has a lower resistance.

If the plug is inserted incorrectly, the EDC will report an overheating condition, and the instrument panel will show a low temperature reading .
Try turning the plug (without using force) .

ulf wrote:

I think you mean "needle bounce," which means the nozzle isn't closing properly.

Ouch... Big fingers... Oh, you mean needle marks.

Quote:

How can something like that happen? Calculus formation, feather breakage...?? Und hast Du Anhaltswerte, wie oft sowas vorkommt ?

The NHG nozzle is longer than the other nozzle needles, and there are more parts in the NHG, so the probability of something like this happening is simply higher (that's my thought on it). Spring breakage... I don't think so... although nothing is impossible.
I once disassembled a leaking NHG (don't try this at home, it was scrap afterwards), and there was terrible grime inside. Where did it come from? I have no idea; it can probably only originate from the fuel. How can anyone know how verschandeln the "broth" we all put in our tanks really is??

Bertil wrote:

Yes, I mean needles.

Hi Bertil.

You were too fast for my lagging thoughts again...
Therefore, I'm following up now:
Ein Nadelhänger müßte doch schätzungsweise das Arbeitsgeräusch des betr. Zylinders deutlich verändern, so daß man als "hörender" TDI-Fahrer nicht unvermeidlich von einem Hänger-bedingten Motorschaden überrascht werden muß . . .

If so, do you have any idea how something like that might manifest itself?

Quote:

I once disassembled a leaking NHG engine (don't try this at home, it was scrap afterwards), and there was an awful amount of sludge inside. Where did it come from? I have no idea; it can probably only originate from the fuel. How can anyone know how verschandeln the fuel we all use really is

?

One could spontaneously react to the alleged organic farm and its statements .
But if the substance has already passed through all the existing filters, I wonder if it might be possible to incorporate an even finer filter .

ulf wrote:

Ein Nadelhänger müßte doch schätzungsweise das Arbeitsgeräusch des betr. Zylinders deutlich verändern, so daß man als "hörender" TDI-Fahrer nicht unvermeidlich von einem Hänger-bedingten Motorschaden überrascht werden muß . . . If so, do you have any idea how something like that might manifest itself?

Um, honestly, I can't tell you whether you would hear it or not. Normally, it should make a terrible clacking and hammering sound.
At the very least, this should reach the ears of every TDI enthusiast.
I just had an idea: It looks like a stethoscope, but it's for mechanics. You can definitely hear it with that, because the sound of the burning is probably unusual.

Quote:

One could spontaneously react to the alleged organic farm and its statements . But if the substance has already passed through all the existing filters, I wonder if it might be possible to incorporate a finer filter

.

Okay, while you can attribute a lot of problems to organic farming practices, things can also be much simpler. This sludge can actually arise from reactions involving various chemicals present in small amounts in regular diesel fuel. You can filter as well as you like, but it will always get through. For example, in France, there's generally 5% RME (biodiesel) in the diesel. So, the diesel is intentionally contaminated. Glycol, water, and who knows what else could be responsible for these kinds of precipitates (I'm not a chemist, unfortunately), but it's the uncontrolled combination of these substances that causes the problem.
It is possible that operating with diesel fuel is just as dangerous as operating with RME.

Hi!

News:

This morning, I tried to start the engine three times (glow plug on, off, on, off, on, off, start), and surprisingly, it started right away. Maybe it's related to my attempts to start it yesterday without actually driving it.
I just preheated the oven twice, but it wasn't enough; however, it was a little better than usual.
After 2 minutes of driving, it started going uphill and I noticed some light white puffs coming out the back, but then just 30 seconds later everything cleared up! So, after that amount of time, the preheating system shouldn't be affecting anything anymore, which now sounds more like it's related to the injectors!?

@Bertil:
If the spray pattern is altered as shown in Henzo's pictures, why is there almost no soot being produced when running at full load (0.000001)? Shouldn't that also lead to the formation of larger particles?


I had the new bearings and seals installed for my ESP pump at Henzo! Very competent pump specialist, I highly recommend them!!!!!!

Henzo mentioned that something like a malfunctioning injection valve would have been noticed.

@Ulf:
Unfortunately, YOUR adapter is not finished yet... so we have to wait.

But: This weekend, my dad's new tires are being installed, and hopefully, we'll have a better idea of what's going on then.

Best regards, Christian.