Kaltstartproplem beim 1Z nicht gelöst *heul* | Posts 176+

Hi Bertil,

If the engine smokes after starting, it's likely that the injection timing is incorrect or that there is no preheating occurring.
The diesel fuel injected before the initial ignition will cause the smoke cloud.

Best regards, Rainer.

Rainer K. wrote:

1,9mg/Hub sind i.O., da hättest Du nichts dran drehen müssen, denn stellst Du die Pumpe fetter ein (Leerlaufwert wird kleiner 1,9mg/Hub), kann es zum bekannten Ruckeln/unruhigen Leerlauf kommen.

Hi Rainer,

It may vary from one car to another, but with the 1.9 engine, Christian occasionally experienced what he called the "vrum vrum" sound at idle.
And in that, I recognized the exact behavior of a car running with an excessively rich fuel mixture, where the engine not only jerks but also can no longer properly regulate its idle speed.

Therefore, my advice to him (based on my experience with AFN) is to start with a dosage of approximately 4 mg.
That also ended the "vrum vrum."
However, I also find it puzzling why it performed better afterwards than before (without start volume adaptation).

Hi Rainer,

I would like to solve the starting problem and not re-flash it .

Best regards, Christian.

haehnlein wrote:

Hi Rainer, I would like to solve the starting problem and not just overwrite it

.

Hi Christian,

Then, please provide us with a summarizing current status update in this gigathread based on your previous interventions.

--> Idle speed at operating temperature according to VAGCOM?
--> Pump setting or control behavior = duty cycle during operation (see my new thread).
--> Starting behavior: warm engine, cold engine, etc.
What other things have been checked and can be ruled out as potential sources of error?

Bertil wrote:

Still not clear after 175 posts???

You are mean "wine" .

This piece of junk... if it weren't so cold...} I would have already taken the ashtray apart into its individual pieces. Why can't I be consistent and sell this thing...?} Unfortunately, I'm a monogamous car owner.}

@Ulf:

I'm a bit confused right now and I don't quite understand the ESP theory yet. Measurement results will be available this weekend.

Preliminary conclusion:

Temperature sensor replaced.

Preheating system is functional.

Compression excluded.

Starting performance is significantly improved and becomes excellent even in very cold temperatures (down to -15 degrees Celsius!).

Starting performance is worst after 2-3 hours of standstill -> cooling water temperature approximately 5-20 degrees Celsius.

Injection volume: 4.4 mg/dose.

Starting behavior when warm (+2 degrees Celsius): starts immediately, but runs roughly for 3 seconds with white smoke.

Consumption: 5 liters.

Best regards, Christian.

Okay... to get rid of that rattling noise, it makes sense.

Best regards, Rainer.

@Christian:

If you read your injection timing in the basic setting mode and compare it to the diagram, does the value match, or not?

Best regards, Rainer.

Rainer K. wrote:

Wenn Du Deinen Einspritzzeitpunkt im Grundeinstellungsmodus ausliest nach dem Diagramm vergleichst, passt der Wert, oder ?

Hi Rainer,

Perhaps the error lies here... I'm going to "measurement blocks," then to 001, and then back, and that puts me at 000. At least, the start of the process seems to be a bit too late here.

y-axis: approximately 40.
x-axis: approximately 110.

Best regards, Christian.

[Please provide the German text you would like me to translate into English.]
Starting behavior at a slight incline (+2 degrees): Starts immediately, but runs roughly for 3 seconds with white smoke.

Consumption: 5 liters

haehnlein wrote:

Hi Christian, With that kind of usage, I don't think anything serious can break

.

I sometimes see white smoke coming from my car in the winter, even after it has started, but without any rough engine running.
Even "dry" diesel exhaust contains some water, which can become visible as white smoke at low temperatures and high humidity.

Does it also produce white smoke when starting if it's only partially cooled down? Or does it then run unevenly?

Okay, here's a theory/question for Bertil and the nozzle experts:
Could it be that a nozzle leaks during idle time and air gets drawn into the nozzle as a result?
Could the diesel that drips into the combustion chamber cause white smoke, while air compresses and is expelled from the nozzle for a few injection cycles before the normal amount of diesel is injected again?
Could the relatively small amount of material used during a warm start require several pumping cycles to initially vent the nozzles?
What about the valves at the pump end of the pipes? Could they contribute to such problems with age?


If the rough idling only occurs during cold starts (@Christian):
Are you sure that :)all the candles will get the necessary power during the preheating phase?
(--> Loose connection in the connector block, etc.)

haehnlein wrote:

Rainer K. wrote: Wenn Du Deinen Einspritzzeitpunkt im Grundeinstellungsmodus ausliest nach dem Diagramm vergleichst, passt der Wert, oder ? Hi Rainer, Perhaps the error lies here... I'm going to "measurement blocks," then to 001, and then back, and that puts me at 000. At least, the start of the process seems to be a bit too late here. y-axis: approximately 40. x-axis: approximately 110. Best regards, Christian

.
As I said, you need to know what you're measuring.
Is the red-marked button grayed out on your end? What happens when you click it?
[img]

If I remember correctly, you then go directly to measurement block 0. Does anyone know this off the top of their head?

Wenn Du nämlich nicht im Grundeinstellungsmodus gemessen hast, sind Deine Werte für den A... http://www.dieselschrauber.de/vag_m_grund.gif

Best regards, Rainer.[/img]

ulf wrote:

With that kind of usage, I don't think anything serious can break . I sometimes see white smoke coming from my car in the winter, even after it has started, but without any rough engine running. Even "dry" diesel exhaust contains some water, which can become visible as white smoke at low temperatures and high humidity. Does it also produce white smoke when starting if it's only partially cooled down? Or does it then run unevenly?

"...I think so too! Perhaps as an important addition: the white smoke is only present when the engine is running unevenly after starting!!! At minus 15 degrees Celsius, it was perfectly clean!!!!"

ulf wrote:

Just a theory / question for Bertil and nozzle specialists: Could it be that a nozzle leaks during idle time and air gets drawn into the nozzle as a result? Could the diesel that drips into the combustion chamber cause white smoke, while air compresses and is expelled from the nozzle for a few injection cycles before the normal amount of diesel is injected again? Could the relatively small amount of material used during a warm start require several pumping cycles to initially vent the nozzles? What about the valves at the pump end of the pipes? Could they contribute to such issues with age?

I had brand new nozzles installed by my father -> no change!

The uneven running, combined with the sound of valves and white smoke, is MOST LIKELY TO OCCUR WHEN THE COOLANT IS STILL QUITE WARM, PREVENTING IT FROM BEING FULLY WARMED UP – FOR EXAMPLE, AT A TEMPERATURE OF 15 DEGREES CELSIUS.

@Rainer:

I will check it again in the default settings mode this weekend.

Best regards, Christian.

haehnlein wrote:

Bertil wrote: Still not clear after 175 posts??? You are mean, "wine".

... why?? Rainer has lost track of things . Otherwise, I'm just a realist!!

Quote:

This piece of junk... if it weren't so cold...

I would have already taken the ashtray apart into its individual pieces. Why can't I be consistent and sell this thing...?

Ulf wrote:

Unfortunately, I'm a monogamous car owner.

"... so I'm with Ulf on this: Nothing serious can possibly be broken."

}
Okay, here's a theory/question for Bertil and the nozzle experts:
Could it be that a nozzle leaks during idle time and air gets drawn into the nozzle as a result?
Could the diesel that drips into the combustion chamber cause white smoke, while air compresses and is expelled from the nozzle for a few injection cycles before the normal amount of diesel is injected again?
Could the relatively small amount of material during a warm start require several pumping cycles to initially vent the nozzles?
What about the valves at the pump end of the pipes? Could they contribute to such problems with age?
}

Jetzt hat der Ulf sogar schon den Überblick verloren. }

I had already mentioned this theory from the very beginning, but Christian experienced the same (or similar) phenomena with the nozzles from his father.

But in principle, that's probably the case.

Bertil wrote:

"... so I'm with Ulf on this: Nothing serious can possibly be broken."

...especially when a diesel engine starts up like a dream in temperatures of -15 degrees Celsius!

Best regards, Christian.

Hey Christian!

I'll say it again (as I already mentioned in the private message):
The more I read this, the more it seems to relate to my problem with the AAT!
If you're not completely comfortable using the VAG-Com yet, why don't you go to a Volkswagen dealer once (just once!) and have them print out the 'Measurement Block 0' (basic settings) for you – it should be free.
And then you compare it to the error database.
After that, everything was clear with me --> the injection start was incorrect --> I had it adjusted (by someone else ) --> and now everything is perfect!

Please don't hit me, I'm not a TDI expert, but I have a strong feeling that Christian's engine is experiencing the exact same problem.

Your 1Z has the exact same problem that my AAT had.
Almost cooled down --> lots of sputtering and smoke, unstable idle.
Extreme cold --> fantastic starting performance.

Hi,
I completely agree with what was said about Markus H.
'My air fuel nozzle had the same problems when the injection start was misadjusted. The poor oil burner would smoke a lot and shake violently during startup. I can also confirm that the starting behavior changes depending on the temperature.'
As soon as the dynamic control system engaged (estimated at 1.5 to 2 seconds), everything was fine (which makes sense if the ESC wasn't completely outside of its operating range).
Before you look for more abstract errors, please check the start of the injection process as described above (in the DEFAULT SETTINGS MODE).
If necessary, I can also offer you a slightly warmer garage located 35 km away .

Best regards, Andy.

Andy wrote:

If necessary, I can also offer you a slightly warmer garage located 35 km away

.

Where exactly?

Best regards,
Uwe