Consumption display approximately 30% higher than measured consumption

Hello everyone.

I'm still having a problem with my Skoda Superb 1.9 TDI PD AWX engine, Elegance model from 2003, originally 96 kW, but with *** tuning since it was new, now producing 114 kW.

The actual measured average fuel consumption is approximately 6.8 liters per 100 kilometers, which is acceptable considering the actual unladen weight of 1620 kg. However, both the current and the average displayed value have suddenly increased by at least 30% over the last 12,000 km (without any modifications to the vehicle).
Previously, the MFA (Multidot) display accurately showed all values with a precision of 2% for approximately 40,000 km.
'Now I'm happy when the displayed value drops below 10 liters. Despite several visits to Skoda and Volkswagen dealerships, the problem cannot be fixed because these control units are supposedly no longer capable of adjusting the fuel consumption display.'
I've tried everything I can think of, but I haven't found anything for this vehicle (control unit).
The vehicle exhibits no noticeable loss of power and does not emit any smoke. It always shifts smoothly to 2000 RPM in the city, and is otherwise not excessively revved; otherwise, the actual average fuel consumption would not be as low as described, namely 6.8 liters.

Does anyone have an explanation for the inflated display and perhaps knows of any possible solutions?

Best regards and thank you for your replies.
Michael.

I cannot believe that there is no possibility for adjustment .

excerpt from http://de.openobd.org/skoda/superb_3u.htm:

Adjust the control unit.

Select STG 17 (combination instrument).
ECU adaptation -> Function 10.

-> Channel 00 (adjustment values) only for WFS-I/II.
Reset customization settings.

-> Channel 02 (Service interval indicator)
To reset, enter '00000' and save the value.

-> Channel 03 (Consumption display)
The base value is 100, and you can adjust the entire range in increments of 5%. The respective maximum values are 85 and 125.

Information can also be found here (further down).

/viewtopic.php?t=8215&highlight=adjustment+of+consumption

TDI-Vielfahrer wrote:

Skoda Superb 1.9 TDI PD Elegance, model year 2003, normally 96 kW, but with *** tuning since it was delivered, now producing 114 kW. I believe it has an AFX engine installed. (I will check exactly tomorrow morning). However, the current and average displayed values have suddenly started being at least 30% too high after approximately 12,000 kilometers, and this has occurred without any modifications or interventions to the vehicle. Bitte gib mir den deutschen Text, den du übersetzt haben möchtest. Hat jemand von euch eine Erkärung für die überhöhte Anzeige und kennt eventuell Abhilfemaßnahmen?

Well, as far as I know, the MFA display is calculated by the AI, using data provided by the MSG.

You could try replacing the current MSG with a different one as a test.
If the consumption is displayed normally, then the problem lies in the modified MSG (Message Sending Gateway).

*** often integrates copy protection processors into their systems (even though OBD tuning would be possible), thereby introducing additional potential sources of errors without any technical necessity: the processor itself, and the numerous manually soldered connections .
There's a good chance that's the reason for your problem. And if my guess is correct, you should be glad as long as there aren't any "real" issues arising from it...

That's why I didn't go to the abbey, after a forum member kindly warned me just in time.

Hello everyone and thank you for your responses.

It's actually an AWX engine; I already changed that in my previous request.

'Definitely, no adaptation to the fuel consumption display is possible on this control unit in the way you described, 'daytrader'.'

I also received the information from 'Ulf' directly from the car dealerships and Skoda, but I thought there might still be a way to find the error in the system and, logically, fix it without replacing the control units. The deviation is over 30%!

'I might have another idea why the display isn't showing the actual fuel consumption. I've been filling my vehicles from canisters with an electric pump, completely full, for about this long, so not a single drop spills. Therefore, I probably need to drive around 250 km before I observe any change in the fuel gauge. If this change in the fuel sender is factored into the calculation (I often refuel after only 200 km without seeing any change on the display at all), it might be causing the inaccurate reading.'
Normally, I would say it should be the other way around, that the MFA (Multi-Factor Authentication) is showing too little information. But maybe someone here has a plausible explanation for this.
But then I don't understand why my Golf IV Variant TDI from 2004 with 74 kW and a PD engine, which doesn't have a chip installed (and never will), isn't exhibiting the same problem.

By the way, I just read the fuel consumption data from the engine control unit in measurement block 15, and it's about 10% lower than the value displayed on the instrument cluster.
Does anyone have an explanation for that?
Subsequently, all values in the engine control unit were reset to their default settings, but nothing changed.


Okay, and now for the less important stuff:

So far, I can only say positive things about *** tuning; the vehicle is running perfectly without any issues and without producing soot.

I can only report negative experiences with ******** Tuning.
Ein falsches Steuergerät geliefert (das ganze sollte damals im Austausch funktionieren) da das Fahrzeug trotz Wegfahrsperrencodierung nicht ansprang, altes Gerät wieder eingebaut und nach Koblenz gefahren, danach lief mein damaliger erste neue Octavia Serie 66kW mit Einnebelungsgefahr, ich traute mich kaum Gas zu geben, also zweite Anfahrt nach ******** wieder einen neuen Chip ausprobiert und das Qualmen wurde um 50% reduziert, aber dafür hatte ich auch keine spürbare Mehrleistung mehr. NAfter 35,000 km, the first turbocharger failed after a 300 km stretch of driving at full throttle. I bought a new turbo and a new original engine control unit (ECU), and then sold the car.

I had a chip installed in my second new Octavia (81 kW engine), and after driving for 500 km with the addition of a sports exhaust system with straight pipes, I was no longer able to read my license plate.
So, I always took a can of wheel cleaner with me to the car wash to remove the soot from the rear of the vehicle. The car lasted until 65,000 km without any engine problems, but the buyer removed the chip immediately after purchasing it.

With the third new Octavia, I managed to stick with the original 81 kW power output.
While it consumes approximately 0.6 liters more diesel on average than the previous two models, I didn't have to hide behind the steering wheel when accelerating!

In the current Superb, the chip was only installed to address the issue of slow acceleration from a standstill, but unfortunately, it hasn't yielded much success because, as is well known, the turbocharger doesn't build up pressure in the lower RPM range, and *** likely can't change other parameters due to the D3 emissions standard.

Best regards,
Michael.

TDI-Vielfahrer wrote:

I have to drive approximately 250 km to observe a change in the fuel gauge, and if this change in the fuel sensor is included in the calculation (I often refuel after only 200 km without seeing any change on the GAUGE at all), could that be causing the inaccurate reading? Normally, I would say it should be the other way around, that the MFA

shows too little information. But maybe someone among you has a plausible explanation for this.

Quote:

When I "overfill" my Polo's gas tank, almost 12 liters more go in than usual. I drive about 400 kilometers before the fuel gauge starts to move. "However, my MFA (Multi-Function Display) shows everything as completely normal – which makes sense, since the consumption is calculated independently of the fuel level."

But then I don't understand why my Golf IV Variant TDI, manufactured in 2004 with 74kW PD engine and without a chip (and never will have one installed), doesn't exhibit the same error.:wink:Because it's not related to refueling.

Quote:

In the current Superb, the chip was only installed due to the poor acceleration, but unfortunately, it hasn't had much success because, as is well known, the turbo doesn't build up pressure in the lower RPM range, and *** probably can't change any other data related to the D3 emission standard.} It seems that: in the "naturally aspirated" range, you can make a TDI run just as poorly by simply chipping it as you could with a purely naturally aspirated engine - unless you turn it back into a fog machine.

I'm likely going to try a larger LLK (SMIC) soon, which hopefully has less internal flow resistance than the standard part. This could potentially shift the charger's spool-up slightly towards lower RPM... we'll see.

Hello.

I have another question regarding this issue for 'ULf,' and of course, for anyone who can offer advice.
What values are included in the calculation of consumption?
Perhaps I can identify the perpetrator by analyzing the data blocks containing measurement values.

Regards,
Michael.

TDI-Vielfahrer wrote:

What values will be included in the calculation of consumption?

Basically, what you need:
Engine speed, fuel injection amount, speed... and for average consumption, also the distance traveled since the last reset.

Quote:

Perhaps I can identify the culprit by reading the measurement data blocks.

I'm curious to see how this turns out, but also skeptical, because if these basic values are already incorrect at the engine management level, the machine wouldn't run normally, or the speedometer/odometer would be malfunctioning.

Hello everyone.
I have finally found and fixed the two problems I described a long time ago with my Skoda Superb equipped with an AWX PD engine. Four new PD injectors were installed this morning, and the fuel consumption display now shows normal values, and the performance after a cold start is back to what it was on the first day. All the optimizations I had made to the engine control unit could also be reset to default values.
Best regards,
Michael.

P.S. By the way, you can buy the new PD elements relatively cheaply from E*** for a reasonable price. Four pieces including shipping cost less than half the price of a new one from a reputable dealer.