Lader kommt im kalten Zustand härter wie im warmen! | Beiträge 16+

Does your 96kW PD also feel like it has more 'bums' when cold?

This could also be related to the fact that, for example, my AAT has a separate "cold engine" injection start field.

In this field, the injection start is controlled to earlier values than in the warm state, which results in a slightly better "injection" performance.

Best regards,
Ronny

[quote="ronny252"]
This could also be related to the fact that, for example, my AAT has a separate "cold engine" spray start field.

In this field, the spray start is controlled to earlier values than in the warm state, which results in a slightly better "spray" effect.
Okay, I understand. Please provide the German text you want me to translate. I will translate only the readable text, leaving the HTML tags, BBCode tags, and URLs as they are.
Hi Ronny,

the idea is sound, but the early timing advance is intended to only compensate for the greater ignition delay at a cold engine.

This is not intended to increase power - however, it could potentially occur if the sensor provides normal values at a warm engine, but the low temperatures distort the readings and thus over-compensate for the actual ignition delay.

This could be checked, for example, by comparing the values from a VAGCOM system for water and air temperature at a cooled engine.

Okay, here's the translation, keeping the HTML tags, BBCode tags, and URLs intact:

"Well, it sounds illogical and crazy, but it's something I've noticed recently, especially when we had almost summer-like temperatures:

My AGR-motor definitely pulls better from the low RPM range when the engine is cold, compared to when it's warm.
Although, theoretically, this shouldn't be the case, the engine produces more power at idle RPM.

Perhaps the wastegate valves on the slightly older turbos tend to stick a little at operating temperature, so they don't close 100%. This leads to a slower pressure build-up and thus a lack of torque in the lower RPM range.
It's just a guess.

Ronny252's explanation also sounds plausible. Maybe it's really due to the advanced injection timing on a cold engine, as the EDC compensates for the increased ignition delay. However, it's true that the combustion process then runs faster, which is also noticeable acoustically through the cold start noise.
This could result in a better response from the engine, which is absent when the engine is warm. However, the peak pressures also increase quite a bit on a cold engine, so it's best to avoid starting a cold TDI.

From the turbocharger side, I can't think of any explanations, because for increasing the enthalpy difference, a higher exhaust gas temperature would actually be advantageous.
Also, cold engine oil hinders the turbocharger's spool-up due to higher viscous friction compared to warm oil.

So, it remains a phenomenon that's difficult to explain.

Best regards,
Alex"

Here's the translation, keeping the HTML tags, BBCode tags, and URLs intact:

The "Rum" rules of the EDC can be easily turned off.

You simply assign all temperature sensors a fixed temperature (a realistic one).

Then, the engine should always be at the same temperature for the EDC, and we can only notice real thermal differences in its behavior: sluggish oil, sticking wastegates, etc.

[quote="donalexo"]
It's possible that this is actually related to the advanced injection timing at cold engine temperatures, as the EDC compensates for the increased ignition delay. However, it is indeed the case that the actual combustion process then runs more quickly, which is also very noticeable acoustically through the cold engine knocking.
Okay, I understand. Please provide the German text you want me to translate. I will translate only the readable text, leaving the HTML tags, BBCode tags, and URLs as they are.
Hi Alex,

As far as I understand, the combustion doesn't start immediately after injection, but rather a bit later.
However, once it starts, all the previously injected diesel burns suddenly instead of "at the rate of the federation".
And this sudden combustion creates the "knocking".

IMO, the increase in pressure and therefore the piston force is not higher than normal, but only steeper, which compensates for the initial delay.

I can't see any better energy efficiency (= efficiency) to explain the perceived increase in performance.

So, I've probably gotten way off track -> Corrections are welcome!

hi,
my lupo 3L also pulls better when cold than when warm.

when the engine is already running warm, I can definitely still notice it.

if I let it stand for a few minutes so that the coolant temperature drops to 60°C, and then start it up, it pulls better than with a water temperature of 80°C or 85°C.

best regards

Hi.

@Ulf: That's correct so far. I just want to add that the fuel isn't inactive during the ignition process, but is actually undergoing chemical reactions. The products of these reactions burn off much more readily than the injected diesel droplets. This gives the "nageln" its metallic sound.

@ Dieselmartin: Coldness does have an effect. The compression work is reduced.

@Powersound3l

Warum steigt die Temperatur bei dir nach dem Erreichen von 60°C an? Sollte die Temperatur nach Erreichen der Betriebstemperatur konstant bleiben, oder ist das bei deinem 3-Liter-Lupo anders?

[quote='konjoy']@Powersound3l

Why does the temperature rise to 60°C after it has reached operating temperature? Shouldn't it then remain constant? Is this different with the 3L Lupo?[/quote]
Hi,
das ist ein selbstgebautes Gerät, das die Kühlwassertemperatur per OBD ausliest und den genauen Wert anzeigt. Deshalb habe ich auch keine Plateau-Funktion.
Viele Grüsse,

Ich meinte natürlich, wenn ich den Motor ausgeschaltet lasse und ein paar Minuten warte.

Oh,

my mistake, I completely forgot that the engine stalls when the 3L Lupo is stationary.