Verbrauchs-Erfahrungen beim Umstieg VP <-> PD? | Posts 16+

Bertil wrote:

For me, this is nothing unusual...

from nothing comes nothing!

That's why I can only give a sad look to the people who drive their gasoline cars with 150-200 horsepower at a slow pace on country roads instead of buying a car with a smaller engine.

Okay, back to the PD engine. I believe the PD engines subconsciously encourage drivers to use higher RPMs. My experience with a 1Z engine and a 100PS PD engine is that the PD engine revs up much faster. Consequently, you have to consciously force yourself to shift at the same RPM as you would with a 1Z. With the 1Z, you tend to shift more often, especially in the city, because the car runs smoother. With the PD, it doesn't matter whether you're driving at 2000 or 3000 RPM in terms of comfort.
I think that definitely plays a role.

x world one wrote:

Bertil wrote: For me, this is nothing unusual... from nothing comes nothing! That's why I can only give a sad look to the people who drive their gasoline cars with 150-200 horsepower at a slow pace on country roads instead of buying a car with a smaller engine.

I completely agree...

and if then there's also the...

On the , there is...

Quote:

Okay, back to the PD engine. I believe the PD engines subconsciously encourage drivers to use higher RPMs. My experience with a 1Z engine and a 100PS PD engine is that the PD engine revs up much faster. Consequently, you have to consciously force yourself to shift at the same RPM as you would with a 1Z. With the 1Z, you tend to shift more frequently, especially in the city, because the car runs more smoothly. With the PD, it doesn't matter whether you're driving at 2000 or 3000 RPM in terms of comfort. I think that certainly plays a role.

Plausible theory. There's definitely something to it.

That's why I can only give a sad look to the people who drive their gasoline cars with 150-200 horsepower at a slow pace on country roads instead of buying a car with a smaller engine. http://www.wolfsburg-edition.info/wbb2/images/smilies/smiley-tock.gif

'I don't judge people who drive a VR6 and use 8 liters of fuel. It's possible to do that without being a traffic hazard (driving 100 km/h on a country road and then slowing down to 50 km/h as you enter a town is, in my opinion, perfectly legitimate and shouldn't be frowned upon). I only judge drivers who treat country roads like highways. But the real problem are the people who drive 70 km/h on country roads and in towns. Those people, along with the speed demons, should really be removed from the road.'

Best regards, WarLord.

Bertil wrote:

Not necessarily, I know of other PD "Artisten" models that initially consumed significantly more, but later ended up using quite a bit less. The engines seem to require an extremely long "normalization" period. In some cases, the fuel consumption (oil - fuel) doesn't stabilize until after 10,000 to 15,000 kilometers. In my opinion, the PD motor requires a slightly different driving style (for lower fuel consumption), which takes quite a long time to get used to. It took me about 8-10 tankfuls to adjust.

Okay, and what exactly, based on your experience, does one need to do differently compared to a VP-TDI engine to drive as fuel-efficiently as possible? (You're torturing us here, grumble. . )

And in what order of magnitude does the normalization effect occur in the cases you are familiar with?

Julian wrote:

Hmm, didn't someone post here before that the maximum injection volume is lower for PDs than for VPEs?

I can't recall anything like that... According to the MFA's instantaneous display, my Polo consumes up to 16.4 liters per 100 km in 5th gear (4000 rpm at 200 km/h) when I'm giving it full throttle. That was the highest reading I've seen so far, around 2500 rpm.
Christel's ALH (4000 rpm at 188 km/h) consumes approximately 12 liters.

x world one wrote:

The PD (direct injection) engine revs up much faster, therefore you have to really force yourself to shift at the same RPM as with the 1Z engine. You tend to shift more frequently, especially in the city, because the car then runs more smoothly. With the PD, that's not the case; it doesn't matter whether you're driving at 2000 or 3000 RPM in terms of comfort. I think that certainly plays a role.

Hmmmtjjaaa... Okay, I'll admit it, the ASZ engine in the Polo runs smoother than the AFN in the G3 or the ALH in the 6K Ibiza.
However, I will initially deny that I accidentally set the ASZ (acceleration control) to a higher value than, for example, the AFN (acceleration control) when accelerating.
If that's the case, it's more likely because the automatic speed control (ASZ) in the low speed range is much more relaxed than the VPs, and I simply "starve" (which still happens to me) when I shift up while going uphill, using my usual shift point.

"@Jan6K: To the extent that it applies, I now confirm your previous experience with the demo 6L-ASZ."
In the flatlands, it's not as noticeable, but in the mountains, the engine simply needs "revs" if you want to move forward. Below ~1400 RPM, my ASZ engine experiences a much more significant drop in power than even the ALH .

Okay, let's talk about daily fuel consumption again: Mostly, I drive on flat roads, and even at 60 km/h and 1000 rpm in 6th gear, with just a slight touch on the accelerator, the car rolls along comfortably. There's no jerking, and even a slight acceleration is possible, which then starts to increase around 75 km/h if you press the accelerator further, and the turbocharger slowly starts to kick in.

ulf wrote:

Aha, and what exactly, based on your experience, does one need to do differently compared to a VP-TDI engine to drive as fuel-efficiently as possible? (You're torturing us here, grumble. . )

Next question...

Seriously, I haven't really thought about it much. Mine has been running low, and the fuel savings from changing my driving style are only about 0.5 liters... so it's not a huge amount.
I feel like my car is rolling better now, which allows me to utilize the torque cutoff more effectively. The braking effect of my ASR (Anti-Slip Regulation) is extremely minimal.

Quote:

And in what order of magnitude does the normalization effect occur in the cases you are familiar with?

That can make a difference of 1-2 liters.

It's probably similar with oil consumption. It's quite normal to use 2-5 liters of oil for the first 15,000 km, but then it can suddenly drop to 1.5 liters per 15,000 km.

Okay, here's my two cents on the matter:
'My old 1.4-liter engine used to average between 5.2 and 5.5 liters per 100 kilometers. I drove about 100 kilometers to work every day, with roughly one-third being country roads, one-third city driving, and one-third highway at around 140 kilometers per hour. The 96 kW TDI engine, with similar driving conditions, consistently consumed about 6.2 liters per 100 kilometers. Okay, it does have about 40 horsepower more.'

I can't say exactly what the current fuel consumption is, as I'm driving 700 km on the highway this week. At an average speed of 170 km/h, it uses about 7 liters. Above 180 km/h, it quickly goes up to 9-9.5 liters.

With a trailer attached, the 1Z needed about 8.5 liters per 100 km at a speed of around 100 km/h. The PD also consumed about the same amount, averaging 100-120 km/h. So, there wasn't a significant difference in fuel consumption. However, you could definitely feel the extra 40 horsepower and the much higher torque.

'I bought an Audi A4 with 110 horsepower (AFN engine) last week to use as a winter car and give it a makeover. Today, I drove it about 500 kilometers on the highway. The average fuel consumption was 5.6 liters, even with some aggressive driving.'

I also have to note, as mentioned earlier, that I tend to shift gears later with the PD system, and I often find myself driving at higher RPMs than I used to with my 1Z.

joergs wrote:

so now, here's my two cents: "My old 1.4-liter engine used to average between 5.2 and 5.5 liters per 100 kilometers. I drove about 100 kilometers to work every day, with roughly one-third being country roads, one-third city driving, and one-third highway at around 140 kilometers per hour. The 96 kW TDI engine, with similar driving conditions, consistently consumed about 6.2 liters per 100 kilometers. Okay, it does have about 40 horsepower more." Bitte gib mir den deutschen Text, den du übersetzt haben möchtest. Last week, I bought an Audi A4 with 110 horsepower (AFN engine) to fix up and use as a winter car. Today, I drove it for about 500 kilometers on the highway. The average fuel consumption was 5.6 liters, with some periods of heavy acceleration.

Hi Jörg,

What are the approximate weights of these three cars?

The extra 40 horsepower should be power-to-weight optimized, and with the same driving profile, it shouldn't actually consume more fuel, since the engine displacement is the same.
Unless one argues that the PD (pre-catalytic device) has a lower overall efficiency due to the finer atomization (higher internal power requirement, see above) -> the old story: higher consumption for "better" emissions .
Then it remains a mystery why my Polo has the same fuel consumption as the AFN Golf 3...

@everyone: Can we roughly estimate how much the supposedly reduced compression translates to in terms of increased fuel consumption (AFN = 19.5, ASZ = 19 according to the catalogs)?

Bertil wrote:

I haven't really thought about it much yet. Mine has run out, and the fuel savings from changing my driving style amount to about 0.5 liters... so it's not a huge amount. I have the feeling that my car is rolling better, and therefore I can better utilize the torque cutoff. The braking effect of my ASR is extremely low.

So, that means you're taking your foot off the accelerator earlier with the AXR Golf to minimize braking, while your older 1Z model was "slowing down faster" as it rolled.

Hmm, I generally let things run as freely as possible and brake as little as I can.
My Polo, for example, requires a more forceful braking action at lower speeds when going downhill compared to the Golf, which I mostly attribute to the tires.

However, this only represents "half the truth" regarding the internal power requirements of the engine. During thrust operation, the pre-injection devices (PDEs) are only "activated without injection," meaning they do not consume any power for diesel atomization.
This internal performance requirement, therefore, does not appear in the rollout comparison...

Oh yeah:
Based on Bertil's experience with increased consumption due to a faulty intercooler, I checked my charge air path yesterday, between the MAF sensor outlet and the EGR unit, by sealing the KGE (exhaust gas recirculation valve) - I did it by breathing into it, but it seems everything is sealed.

Hi Ulf,

ulf wrote:

So, that means you're taking your foot off the accelerator with the AXR Golf earlier, so you have to brake as little as possible, while your older 1Z model was "slowing down faster"?

That's right. I can't say exactly what's causing it. What's certain is that the higher weight is contributing, as it simply puts more stress on things. The tires are roughly the same width and from the same manufacturer (195/50*15 on the 1Z; 195/65*15 on the AXR, both on 7*15 inch rims).
I filled the transmission with SLICK50 (for transmissions) because it was shifting poorly in the cold. This effect is now somewhat better, but I feel that the car rolls better since the treatment. The observed reduction in fuel consumption of 0.1 liters is likely within the measurement tolerance and has only occurred over 6 tankfuls.
The Slick50 was just an experiment, since the product was already on the shelf. Normally, I believe that such additives don't do much (or anything).

Quote:

But that is only "half the truth" regarding the internal power requirements of the engine. In thrust mode, the PDEs are only "activated" without actually injecting any fuel, so they do not consume any power for diesel atomization. This internal performance requirement, therefore, does not appear in the rollout comparison...

Okay.
However, with PD (presumably referring to a specific material or process), the lower density may result in better spreading or leveling properties.

Hmm, I generally let things run as freely as possible and brake as little as I can.
My Polo, for example, exhibits a more pronounced deceleration when going downhill in coasting mode compared to the Golf , which I mostly attribute to the tires.


It wasn't just about the tires. I've found that cars and engines with higher mileage often run better than brand new ones with lower mileage. Although the comparison was between a gasoline engine and a diesel engine, and diesel engines have a higher compression ratio, my 1Z (in a Passat with 174,000 km) performed better than a Golf IV 1.6 16V with 50,000 km, and even better than our company Polo with just under 15,000 km and the 1.2-liter engine.

Best regards, WarLord.

Hi,

I just returned from Braunschweig, and during the trip, I conducted some interesting fuel consumption tests on the A2 highway... with the goal of increasing the fuel consumption, which I was quite successful in achieving.

We filled up the tank just before Magdeburg, and then headed west, maintaining speeds between 190 and 210 km/h according to the speedometer (briefly reaching 215 km/h going downhill). So, almost always full throttle, except for a 15 km stretch where I used the cruise control at 190 km/h. We continued like that until just before Braunschweig, where the speed limit drops to 120 km/h. The car was loaded with three people, a little luggage, and a full tank.

That was a distance of 110 km, for which the MFA (Multi-Function Display) showed an average of 173 km/h in real-world conditions – measured from the moment of departure at the charging station to the point where the car was slowed down to 120 km/h.

The average fuel consumption was 10.5 liters! ...which I also consider to be realistic, as the instantaneous fuel consumption (ASV) at full throttle in 5th gear ranges from 13.5 (at around 2000 RPM) to 11 (at >4250 RPM).

Best regards,

Jan.

WarLord wrote:

I have experienced that cars and engines with higher mileage tend to run better than brand new ones with lower mileage. Although the comparison was between a gasoline engine and a diesel engine, and the diesel engine has a higher compression ratio than a gasoline engine, which should put the diesel at a disadvantage. However, my 1Z was not like that.

Hi,

Generally, diesel engines tend to roll more easily in overrun (engine braking) than gasoline engines, because the latter also have to overcome pumping losses during engine braking.
The diesel engine compresses air during the intake stroke, as usual, but this air releases its energy again during the "dead center" phase -> theoretically, this eliminates pumping losses.

If you roll a gasoline engine with the throttle open, turn off the ignition, and then give it full throttle, it will brake less (like a diesel engine) because the pumping losses are largely eliminated.

Hey guys, don't forget about air resistance!

When I see Jan's record, I realized that with an average speed 3.4 km/h slower, I still managed to achieve a fuel consumption of 3.4 liters/100km, which is more economical. This Golf-class shape is quite aerodynamic compared to my sedan.

Then I'd like to add my two cents.

I owned an A4 Avant 1.9 TDI with 81 kW (MJ96) from 2000 to 2002.
I drove this thing for 74,000 km (as a field service technician).
Fuel consumption: between 4.9 and 7.2 liters per 100 kilometers, average across all driving conditions: 5.6 liters.
(7.2 was towing capacity, vacation: 1200KG caravan to Normandy).

From 7:02 to 11:03, I had a Golf 4 1.9 TDI ATD with 74 kW.
It covers approximately 50,000 km, just like the previous A4 .
Fuel consumption: between 4.9 and 7.5 liters per 100 kilometers per tank, average across all conditions: 6.2 liters.
(7.5 tons, occasionally used for short-distance transport of construction debris).

Now I have the A6 (profile).
Fuel consumption: between 6.2 and 8.6 liters per 100 kilometers per tank, average across all conditions: 7.5 liters.
(8.6 liters were used for 400km of highway driving with an average speed of 180 km/h, the rest of the tank was used for normal inland driving).

I was initially very impressed with the Porsche Taycan due to its design and acceleration.
'However, it tends to be thirsty at higher speeds and only offers fuel efficiency with very gentle driving or when using cruise control.'
It's truly fuel-efficient at relatively low speeds.
The A4 was quieter and more fuel-efficient, and the increased fuel consumption of the V6 is perfectly acceptable to me.
The instantaneous fuel consumption (FIS) was high for both the PD and the V6 engines at high speeds.
almost the same (cruise control at 180 km/h, flat road, same tires, approximately 11 liters).

Hello everyone!

I compared my ASV (see signature) with my colleague's 100 HP PD Golf IV (engine code unknown). Since we both have a fairly similar driving style (very conservative), this should largely eliminate the driving style as a major factor in the fuel consumption differences. What's surprising to me is that the lighter Golf needs significantly more fuel than my Octavia Combi with roof rails. When the Golf shows 4.1 liters per 100 km on the display, my Octavia shows 3.7 liters under almost identical conditions. This difference is also roughly confirmed at the gas station. When my colleague shows up with his wife's Golf IV Kombi (also 100 HP PD), he uses another half a liter more. I then jokingly call it a "fuel guzzler."

I have long considered the PD engine to be a good step towards optimizing fuel consumption. The first PD engine with 115 hp in the Passat, for example, had a very low fuel consumption in "auto motor und sport" tests. This leads to the assumption:

ulf wrote:

Higher fuel consumption for "better" emissions

ulf wrote:

If that's the case, it's probably because the ASZ (Automatic Speed ​​Limiter) in the low RPM range is much more relaxed than the VP's (Variable Valve Position), and I simply "starve" (which still happens to me) when I shift up while going uphill, using my usual shift point.

And that's why I love my ASV. It pulls from the lowest RPMs. Sure, when the turbo boost kicks in, it adds a lot more power. But even below that, there's so much power that you have to be going uphill quite a bit before you start to feel like you're "starving" for more. My extreme test in that direction (flat road): 42 km/h = idle speed to 100 km/h (speedometer 107) in 17.7 seconds.

Regards,
mcgregg

durnesss wrote:

was initially enthusiastic about the PD due to its suit/acceleration, "However, it tends to be thirsty at higher speeds and only offers fuel efficiency with very gentle driving or when using cruise control." It is truly economical at

not high speeds.
Hi,

It seems that's how it is, at least so far.

However, I only have the comparison between the ALH-Ibiza and the ASZ-Polo engines, which is a bit skewed because they have 90 and 130 horsepower respectively (my AFN-Golf didn't have MFA).

However, it seems to me that a single acceleration, for example from 70 to 110 km/h in 5th gear (where both cars have approximately the same gear ratio for rpm to km/h), meaning the same "task," will increase the average fuel consumption of the Polo to a greater extent than it does in the Ibiza.
Assuming, of course, that the reset of the consumption memory always occurs at the same point, otherwise the entire comparison wouldn't be valid.

Here's another update:

Since it has gotten slightly warmer in the past few days, my car's fuel consumption on my daily routes has also decreased by about 0.3 liters (according to the MFA's single-trip average).

I've never noticed such a temperature dependence with the AFN before.
Okay, he didn't have MFA enabled, but even when refueling, the differences in fuel consumption weren't nearly as significant given such a small temperature change.