Does diesel soot affect climate change?

Today I noticed that my engine is producing a lot of black smoke when accelerating, especially when the air conditioning is turned on.

If I turn it off, the soot disappears!

Why? According to my boost gauge, the boost pressure is the same as before. I understand that the fuel injection amount is increased at idle to compensate for the heavy load of the air conditioning compressor, but shouldn't it be reduced again from idle speed onwards?

Regards,

Manuel.

Hi,
I don't know whether it *has* to be that way or if it *should* be, but in my car, it's the same.

Am I sensing a potentially affordable tuning opportunity here?

Could people who don't use the climate control system potentially utilize the climate control input to increase the fuel injection volume by a fixed amount of X mg per cycle? And would these X mg possibly not be subject to any fuel injection limit? If it is indeed possible for you to generate soot only through the climate control system, and nothing else, then that sounds suspiciously like a tuning possibility...

Regards,
Private individual, who already has a [specific item/resource] and therefore will not be using this opportunity.

Why? According to my boost pressure gauge, the boost pressure is the same.


'This is because the amount of fuel injected is increased across the entire RPM range. Please log the fuel injection quantity; in this case, boost pressure is not relevant.'

...der eine Klima hat und diese Möglichkeit somit nicht nutzen wird.

Hi there,

wieso sollte man das nicht nutzen. Man müßte nur eine Möglichkeit finden, den Klimabetrieb vorzugaukeln, obwohl die Klima auf ECO steht.

Greetings.

Eike.

Does that mean that when the compressor is activated, the fuel injection amount/power increases?

I honestly don't feel any difference between the Eco and Climate modes, except for how smoothly it rolls.

Best regards,
Uwe

wieso sollte man das nicht nutzen. Man müßte nur eine Möglichkeit finden, den Klimabetrieb vorzugaukeln, obwohl die Klima auf ECO steht. {M

Simulating a permanent climate control operation would not be difficult. Simply connect the corresponding input on the engine control unit (ECU) to ignition power continuously (for AHU T68/37). To do it properly, you could also connect the climate deactivation output of the ECU (AHU: T68/2 via a relay in such a way that it can switch off the climate input of the ECU if necessary.

However, you will then lose the comfort function that this input actually provides. In simpler terms: Every time the air conditioning compressor starts or stops, the engine control unit won't detect it (or only detects it through a change in speed at idle). This means there will be a jolt each time the compressor turns on or off.

Conclusion: I believe this tuning option (if it even is one, which seems to be the case) is only suitable for drivers who don't care about fuel efficiency or for those who are willing to tolerate the jerking motion.

wieso sollte man das nicht nutzen. Man müßte nur eine Möglichkeit finden, den Klimabetrieb vorzugaukeln, obwohl die Klima auf ECO steht. {M

'...However, you will then lose the comfort feature that this input actually provides. In simpler terms: Every time the air conditioning compressor starts or stops, the engine control unit won't detect it (or only detects it through a change in RPM at idle). Therefore, there will be a jolt each time it turns on or off...'


Hi there,

Isn't it the case that modern climate control compressors no longer simply turn on and off? I seem to recall reading something about them being regulated now, meaning that the compressor's output can be adjusted to match the required cooling capacity.
On my ALH with air conditioning, it seems to be the same. When it's really hot, the idle fuel consumption increases to up to 1.4 liters per hour. If only a small amount of cooling is needed, the idle fuel consumption is between 0.5 and 0.8 liters per hour.
According to this, there should be no noticeable jolts or jerks, except possibly when switching from ECO to AUTO mode.
Greetings.

Eike.

That's exactly right. Modern compressors have a variable stroke thanks to a wobble plate, and they adjust the cooling capacity to meet the demand.

My Audi, manufactured in 1990 and equipped with an R12 refrigerant and an older system, almost stalled when the compressor kicked in.

Best regards,
Uwe

He must have been really cool, right?

Best regards, WarLord.

However, he had it. I still miss it today. No matter how incredibly hot it was outside, within a very short time, the car would have perfect air conditioning.

"Today, things are different. My newly installed system needs a lot of speed and time to reach a barely tolerable level of comfort. Even on longer journeys, the system only just manages to achieve a pleasant temperature. In extreme weather conditions, I even have to press the recirculation button."

Best regards,
Uwe

Hi there.

two things:

'A properly functioning TDI engine will not produce excessive smoke even with increased fuel injection, regardless of how much more fuel is injected. Furthermore, even with a modified control unit that provides 15% more power, it still doesn't produce excessive smoke.'

2. There are swashplate compressors that are controlled internally and externally. The 'older' models in ALH and similar vehicles have internal control. They adjust their performance continuously within the range of 40-100% and are regulated by the pressure difference between the low-pressure and high-pressure sides.
Extern controlled compressors are started by a PWM signal from the climate control unit, always run continuously (and therefore have a safety clutch on the pulley), and can be adjusted steplessly from 1% to 100%.

I'm sorry, but I cannot access external websites or specific files online. Therefore, I am unable to translate the text from the provided URL.
-> technical article on air conditioning systems (exclusive to dieselschrauber.de)

CU Gremlin.