leicht OT: Fahreindrücke Vergleich PD-VP | Posts 24+

Hi,

To keep the average speed "low," even a short stretch without using full throttle is enough.

"My extreme was about 70...100 km (I don't remember exactly) on the A2 highway, right after refueling and resetting the trip computer. I was essentially driving at full throttle (at full throttle in 5th gear, the instantaneous fuel consumption for my car is around 12...13 l/100 km), and at the end (i.e., near the 120 km/h speed limit signs before BS), the display showed an average of 10 l/100 km – a result of some traffic-related slowdowns. The average speed for that section was 172 km/h, while my speedometer indicated around 190...205 km/h."

Okay, let's get back to the topic: @Ulf: Did the camshaft adjustment change anything about the weakness at engine speeds below 1500 RPM?

Best regards,

January.

Oops, I may have started a megathread .

Well, since it's such a pleasure, here are two more notes.

The fuel consumption with the Passat Estate was surprisingly low at 7.7 liters per 100 km, even with a very brisk driving style. Almost exclusively on highways (A7) and speeds between 180 and 220 km/h. The MFA (Multi-Function Display) often showed over 14 liters per 100 km. I had feared something worse, but the refueling stop taught me otherwise .

"I also noticed a certain tendency for the power drive (PD) to jerk or shudder in the partial load range. There was a very narrow speed band within which it didn't function smoothly; outside of that, it would jerk quite noticeably."

Regards,
Alex.

By the way, our 100 horsepower PD engines can be easily stalled. It doesn't even take a jerky start. They don't like starting without gas or with very little gas, and they reward low-RPM driving by stalling. A perfect example is when you're looking for a parking space and are moving at just slightly above walking speed in second gear. Our PD engines often respond to acceleration by stalling. Also, they don't feel as smooth at 1100 RPM as my 1Z engine does.

I was a bit disappointed with the expected top speed. My old 1Z reached a maximum of 200 km/h according to the GPS. Our Variant 100PS PD just manages to reach that speed according to the speedometer, and on a flat road, it's more likely to be limited to around 180 km/h. With a longer stretch of open road, you might be able to reach 190 km/h.

The fuel consumption is too high for me, but it might be due to the heavier variant. I can't seem to get the car below 6 liters per 100 kilometers. But you shouldn't rev it above 2000 RPM, especially with a good ~50% proportion of country roads! My 1Z uses a more pleasing 4.9 liters .

I attribute this phenomenon to the fact that our diesel engine cannot be run at such low speeds. I drive through the town in fifth gear with the 1z, which is not possible with the diesel engine, or it would be very stressful. So, you end up driving in fourth gear, which consumes more fuel.

However, to be fair, the PD likely weighs approximately 250 kg more.
(Golf4 Variant with large navigation system, climate control, electric windows, electric parking brake, ESP, ABS, alloy wheels, rain sensor, multi-function steering wheel, heated seats)

What I like most about the PD is the noise level .

@Manuel V: The 330d is a 2003 model, and there were likely at least three different versions of this engine. The first had somewhere between 180 and 190 horsepower, one had just over 200 horsepower, and the current version in the 5-series BMW has more than 220 horsepower and 500 Nm of torque.

@PD-Drivers

If you want a motor that performs better at low RPMs and has more responsiveness, try replacing the small intake snorkel with one of a larger diameter. The effect is a combination of what's essentially a 'faulty' EGR system (which allows the turbo to spool up faster) and a modified throttle pedal sensor (which makes the engine respond more directly to the accelerator).

I was inspired by Ulf's article and replaced the intake pipe to the air filter on my Golf IV 100PS-PD AXR engine with a flexible hose, 60mm in diameter. I left the airflow ducting from the grill and behind the headlight as is. The flexible hose is about 5 cm shorter than the original. A 70mm or 80mm hose would also fit. It's flexible because the air filter opening is oval.

The engine responds better to the throttle and revs up more smoothly. In first gear, it felt like the engine had less power than in second gear. That often-mentioned sluggishness is also gone. Subjectively, you have about 200 RPM earlier where you feel more power.
I haven't been on the Autobahn yet. Top speed has never been a problem for me. I always reached around 200 km/h (approximately 124 mph) according to the speedometer at about 4200 RPM.
I prefer the one with the larger intake manifold. It's quite close to what the VP reported. However, I haven't driven either of them yet. The AXR is my first diesel.
It didn't run as well without the intake manifold.

The AGR is still 'okay.'

One wonders what Volkswagen has done to deserve this.

(all information is subjective)

Jan6K wrote:

@Ulf: The camshaft correction didn't change anything about the weakness below 1500 RPM, did it?

No, it doesn't look constricted from the top anymore.

powermac wrote:

Inspired by Ulf's expert article, I replaced the intake pipe to the air filter on my Golf IV 100PS-PD AXR engine with a flexible hose with a diameter of 60mm. I left the airflow from the grill and behind the headlight as they were. The flexible hose is about 5 cm shorter than the original. A 70mm or 80mm pipe would also fit. It's flexible because the air filter opening is oval. The engine responds better to the throttle and revs up more smoothly...

I wouldn't have thought that it could provide a benefit even at low speeds (because normally, no vacuum is created in the air filter box at that point).
Perhaps it's due to the 5 cm shorter length -> resonance effects...?

Where can I find flexible pipes with a diameter of 60mm?
I've only seen 100 and 125 caliber cartridges (or something similar?) in hardware stores so far.

Looking at the original pipe, it becomes clear that its opening is probably only about half the size of the air filter housing. It takes quite a while for any airflow to develop through such a small opening. This could also explain why the engine hesitates when trying to accelerate. The engine seems to be running out of air.
Furthermore, this vacuum also affects the control valves (e.g., AGR, VTG). The large pipe allows them to be purged more quickly. This is something that shouldn't be overlooked. Even small things can make a difference.
Unfortunately, I don't have a digital camera, so I can't provide any pictures.

It's baffling to me why they installed that component. They're probably trying to squeeze every possible decibel out of it. It makes the engine sound just a little bit louder, with this sort of rumbling undertone. Subjectively, it's extremely subtle, but at VW, it's all about the objective measurements from instruments. However, compromises are inevitably made in the process.

You can find flexible pipes up to 60mm in size at stores like ATU. In my case, I had to wrap the pipe with tape because its diameter was slightly too small for the air filter housing. Eventually, when I have the time and inclination, I'll use a heat gun to shape a new one from a plastic pipe, as the inside of the flexible pipe isn't smooth.

powermac wrote:

When you look at the original pipe, several things become clear. The opening is estimated to be only half the size of the air filter housing. It takes quite a while for any airflow to build up. This could also explain the reluctance to rev up. The engine seems to be running out of air.

Generally yes for a naturally aspirated engine, but with a TDI engine, the turbocharger will likely come loose again - although of course not for free -> see technical article.

Quote:

Furthermore, this vacuum also affects the control valves (AGR, VTG, etc.). The large pipe allows them to be ventilated more quickly. This should not be neglected. Even small things matter.

I don't care at all.

You could try using the original pipe and instead of taking the pneumatic pressure from the air filter box, feed it "openly" through a fuel line filter or similar. There's absolutely no way you'll feel or measure any difference in performance.

Quote:

Flex pipes are available up to ATU. Up to 60mm.

Okay, thank you!

Hello!

I often hear about problems with engines that stall unexpectedly.

There's a campaign at Volkswagen where a control unit with an updated software version is being installed as a replacement.

If the vehicle has an unstable idle with noticeable misfires during the warm-up phase, and it's a 130 or 150 horsepower common rail diesel (PD) engine with the older software, then a replacement is necessary. I know this for sure in the case of the Golf!

I also experienced that problem, although very rarely.
We started driving, stopped at the next traffic light after about 500 meters, and noticed slight misfires, while idling.
When the clutch pedal is pressed, they disappear.

After replacing the control unit (under warranty!), the problem was resolved, and as a positive side effect, stalling is now hardly possible anymore !

You can even start the engine without using any gas, unless you want to do a "gentleman's start"!

For my acquaintances with a 150 HP direct-injection Golf, the difference after replacing the component was even more extreme; you had to be very careful and use a lot of finesse when engaging the clutch to avoid stalling the engine. - Afterwards: completely stress-free!

It would be worth checking whether these problem vehicles are also covered by this campaign!

You might as well give it a try!

P.S. I'm driving a 2003 Golf ASZ!
Starting at 4500 RPM, my engine also becomes a bit sluggish!

I don't have a diagnostic tool at home because I unfortunately have a laptop with a USB port, and spending 300 euros on one seems like too much.

I'll check my records to see if I can find anything.

The modified control unit will be available starting at the beginning of this year!
I have no idea when this was incorporated into the series!

Ulf wrote:

Quote:

Hmm, could you please read out the part number and software version of your engine control unit (ECU) as a "reference" for others?

Here are my documents!
Excerpt from HST2:

Problem Description
Rough idle during the warm-up phase.

Cause
The engine runs unevenly between 20 and 70 degrees Celsius coolant temperature. Inside the vehicle, this irregular engine running is also noticeable as misfires. When using the manual transmission, the engine runs normally when the clutch is engaged.

Serial Solution
Deployment of new software:
96 kW ASZ MJ/03 with manual transmission, data version 5259.
110 kW ARL MJ/03 with manual transmission. Data version: 5352.

KD solution
Please compare the required control unit based on the table below and order the corresponding solution through ET-Kassel.

Predecessor----------Successor---------------Data Status
+++++++++++++++++++++++++++++++++++++
038 906 019 FG ----- 038 998 019 A ----------------- 5362
+++++++++++++++++++++++++++++++++++++
038 906 019 HJ - Manual transmission / 4-Motion - 5259
-------------------------038 906 019 HJ

-----------------------Automatic Transmission--------------5363
-----------------------038 998 019 B
++++++++++++++++++++++++++++++++++++
038 906 019 HH---038 906 019 HH----------------5352


I hope this is detailed enough!
Therefore, I now have a data count of 5259!

Has anyone ever driven a Porsche without stalling it, even once? (I've managed to do it many times myself.)

When I think about the V6 engine, it runs on the country road at a low speed, only between 1000 and 1400 RPM, almost like a tractor .

Okay, the V6 simply has more rotating mass, so it's harder to get it going quickly. The PD engine becomes more flexible with increasing mileage; I only had a few instances of stalling in the first 5000 km. However, that was also because my previous Golf 4 ALH had shorter gearing (and significantly so!), which meant you couldn't rev the engine up as easily.
Everything is a matter of getting used to it, and with sufficient mileage, the PD can also handle lower RPMs, which makes it less sensitive.

loveme wrote:

Here are my documents! . . .I hope this is detailed enough! Therefore, I now have a data count of 5259!

Okay, that's enough.
Thank you .

Hello everyone!

Today, I had another opportunity for a thorough PD test (which is why business trips are so useful for so many things ).
This time, it was a Golf with the 1.9 TDI engine and 77 kW. I find this to be a very well-balanced power output. The "smaller" 105 hp engine pulls much better from low RPMs than the 130 hp version. The way the torque is delivered is much more harmonious, and also less dramatic. There was no sign of sluggish acceleration or tendency to stall.
The Turbosound is simply brilliant . Even the slightest movement of the accelerator pedal, even from idle speed, modulates the Turbosound. It's almost addictive!
Primarily, abrupt changes in throttle position when shifting or releasing the accelerator pedal cause the turbocharger to produce a louder, more pronounced whistling sound.
The engine also works very well with the 6-speed manual transmission. You can always find a good gear ratio.
The fuel consumption was also quite good. During a brisk drive on country roads and a short stretch on the highway, the consumption was just under 5.5 liters per 100 kilometers.
I also find the MSG's throttle response interesting. When coasting and briefly, for fractions of a second, lightly touching the accelerator pedal, you can still hear a faint ticking sound from the injectors long after your foot has left the pedal. This is a clear indication of a heavily dampened and smoothed target value control.

Okay, that's enough.

Regards,
Alex.

P.S. I can easily imagine that with a moderate performance increase based on this engine, you could achieve a well-balanced 130 horsepower vehicle.

Hi Alex!

Have you also noticed a strong dependence of the 'seat pressure' on the load cell (LD)?
To me, it seems like that's the case. For example, if you press the accelerator pedal firmly at 2000 rpm, you immediately feel some thrust. But things really take off a little later, when the turbo pressure kicks in. You can practically feel the turbo spooling up. This suggests to me that there is a strict limit on emissions.

Sure, here is the translation of the text from German to English:

'VG' translates to 'Very Good' in English.
Joe.