Ruckeln bei 1Z lokalisiert. Was nun? | Posts 16+

Hello,

Compared to the data from the error database, this actually looks quite good...

Ad group 1.

Field 1: Motor speed.
Display: Target: 861..945 RPM.

Field 2: Injection volume.
Display: Target value: 2.2 - 9 mg/H.

Field 3: Sensor voltage, control slider position.
Display: Target voltage: 1.25 - 1.7 V.

Field 4: Coolant temperature.
Display: 80..110°C (Indication)

Hi Michael,

You're right, I could have looked that up.
If data is available for the specific engine being analyzed, one should definitely not resort to "only similar" engines.

Hello!

New fuel injection pump installed - the jerking is gone. It was definitely due to the fuel quantity control unit.
It probably could have been installed by a Bosch service center, but I got the pump for 370 EUR, which was cheaper than having it installed.
Here are the new measurement values. Measurement block 1.

Idle speed.

old - 903 RPM, new - 903 RPM.

Injection volume.

old - 2.6 mg/H, new - 6.2 mg/H.

Voltage sensor, control slide position.

old - 1.36 V, new - 1.60 V.

Coolant.

old - 88.2°C, new - 85.5°C

Regards,
Detlef.

Detasz wrote:

Injection volume. old - 2.6 mg/H, new - 6.2 mg/H. Voltage sensor, control slide position. old - 1.36 V, new - 1.60 V

Hi.

That seems to confirm my initial suspicion that the old fuel pump was definitely "running too rich" even when idling.

Depending on how the pump settings differ, you might be experiencing less power now... have you noticed anything like that?

The engine feels a bit sluggish from the bottom end – that is, until the turbocharger kicks in. Is there a way to fix this?

Detlef.

Detasz wrote:

In the lower RPM range - that is, until the turbocharger kicks in - it feels a bit sluggish. Is there a way to fix that?

Hi.

Basically, yes (by readjusting the new pump), but then you would most likely experience the jerking problem again.
A lot of power before the turbo kicks in is only achievable without any lag, as far as I know, through chip tuning.

If you don't notice a significant lack of power in your car's 2000-4000 RPM range, be happy that it's no longer misfiring – and that your car will likely pass the emissions test more easily.

ulf wrote:

Detasz wrote: Injection volume. old - 2.6 mg/H, new - 6.2 mg/H. Voltage sensor, control slide position. old - 1.36 V, new - 1.60 V Hi. That seems to confirm my initial suspicion that the old fuel pump was definitely "running too rich" even when idling. Depending on how the settings of the pumps differ, you might now have less power... have you noticed anything like that yet?

Hi Ulf,

Why would the old pump be "too rich"? Doesn't the new pump tell the control unit to use a higher injection value, so shouldn't the new pump be "richer"?
Or am I making a mistake in my thinking?
The old pump was already operating close to the lower tolerance limit, with a leakage rate of 2.3 mg/hour.

Hi Bertil.

"The 2.6 and 6.2 mg figures are just the amounts that the engine computer *thinks* it should inject."
At most one of the numbers can be correct as a real number.
What do you think the actual idle speed would be with the new pump, if you suddenly started feeding the same engine approximately 250% more fuel than it was previously getting?

Let's arbitrarily assume a real-world value of 5 mg/KH, which is what it takes for the warm engine to maintain 900 rpm.
If the old pump appears to inject only 2.6 mg (= RWG value), it is simply injecting too much fuel compared to its own RWG output signal.
If the new pump already shows a reading of 6.2 mg, then it is functioning correctly.
set at a rather thin, or even underweight, level.

That's how I see the matter, at least... when dealing with sensor signals in controlled systems, you sometimes have to "think outside the box" .

Hi Bertil.

I just remembered something else:

At idle, the engine speed is the primary target variable for the control processes.
For example, you can often tell how the engine control unit "reacts" when you accidentally slow down the moving vehicle below 900 RPM without disengaging the clutch.
Or, how effortlessly you can start on inclines without using the accelerator.

During operation, the focus shifts from the engine speed to the target value of "fuel injection quantity," which is determined based on all relevant parameters and maps.
That's why power boxes work, as they only distort the RWG signal. If the motor control unit treated the RWG signal the same way as it does during idle, then a power box wouldn't be able to achieve any significant increase in power.

Somewhere above the idle speed, there must be a transition point between the "priority speed" and the "priority fuel injection amount."
If the engine is already producing too much power or reaching excessively high RPMs for the transition, despite what appears to be a low injection quantity (e.g., the pump is set too rich or due to a "10c" tuning), there might be a kind of conflict between the two control strategies (where prioritizing RPM provides more torque than prioritizing injection quantity).
Alternatively, the EDC switches between the two strategies, and the constant interruption manifests as stuttering.

What do you think of this explanation?

ulf wrote:

Hi Bertil. ... Somewhere above the idle speed, there must be a transition point between the "priority speed" and the "priority fuel injection amount." If the engine is already producing too much power or reaching excessively high RPMs for the transition, despite what appears to be a low injection quantity (e.g., the pump is set too rich or due to a "10c" tuning), there might be a kind of conflict between the two control strategies (where prioritizing RPM provides more torque than prioritizing injection quantity). Alternatively, the EDC switches between the two strategies, and the constant interruption manifests as stuttering. What do you think of this explanation?

Hi Ulf,

That corresponds to what I've always maintained: a resonance phenomenon. The transition between the areas is certainly critical, and the fact that this vibration occurs within a specific speed range makes logical sense. I hadn't even thought of that.
If "audifan" had provided more information about the TDI software, we could have confirmed or denied it.

I need to think about the fuel injection amount a bit more, but your explanation is okay.

Hi Bertil.

Rainer has just eliminated the "roll-over" vibration from his AHF (presumably a piece of equipment) by adjusting the control mechanism.
The idle injection volumes he posted (in the thread about DIY solutions for misfires in the error database) confirm my theory:

Original at 2 mg: Jerky movement and full power.
Starting at 3 mg, you'll experience less jitteriness.
With 6 mg, there's no more stuttering, but there's a loss of performance.

--> That is, the pump appears to be running leaner at the "6 mg" idle air flow value than it does at lower mg values.

Hi Ulf,

... but mine vibrates no matter where the control panel is located. The intensity of the vibration (i.e., how noticeable it is) is more pronounced with a "heavier" setting.
I am currently unable to perform measurements with VAG Com (the Lappi hard drive is broken !!!).
But now I've noticed that the jerking at 2000 RPM is less noticeable when the auxiliary heating system is turned on.

Bertil wrote:

My device vibrates, but it doesn't matter where the control panel is located. The intensity of the vibration (i.e., how noticeable it is) is more pronounced with a "stronger" setting. I am currently unable to perform measurements with VAG Com (the Lappi hard drive is broken !!!). But now I've noticed that with the auxiliary box turned on, the jerking at 2000 RPM is less noticeable.

Hi Bertil,

It seems that your stuttering might be coming from somewhere else, rather than the symptoms that I've been able to trigger (or disable) so far.
It particularly contradicts my experience that using an active speaker system results in less noise.

Do you have an inductively coupled RWG?
If so, my little toolbox is probably at the end .

Hi Ulf,

Yesterday, I had the opportunity to test a different pump (I had a different one installed), and I can drive with it for a few days (it will be removed again on Saturday ).
THE SHAKING IS GONE!
I hope to have my laptop working again by Saturday so I can use it for measurements.
I'm not going to overemphasize the fact that the engine doesn't seem to be misfiring when the device is turned on, as that's very subjective. Just assume that it might be misfiring (though not noticeably).

I cannot tell you which manufacturer produces the VE4/10 E 2250 R 510-1 (0460404985) pump.

Bertil wrote:

It is the VE4/10 E 2250 R 510-1 (0460404985) pump.

I cannot tell you which RWG it has. }

Hi Bertil.

Hold an ohmmeter between pump cable 1 and 2.
Measurement value of 6 ohms --> inductive sensor.
Measurement significantly higher --> more susceptible to wear.

Is the performance curve largely the same for both pumps?

ulf wrote:

Hi Bertil. Hold an ohmmeter between pump cable 1 and 2. Measurement value of 6 ohms --> inductive sensor. Measurement significantly higher --> more susceptible to wear. Is the performance characteristic of both pumps largely the same?

I can tell you that from memory: approximately 5 Ohms.