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Low RPM = High Fuel Consumption

 
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Mephisto
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Post05-02-2005, 20:00    Subject: Low RPM = High Fuel Consumption Quote

Hi everyone,

Here are two things that bothered me about my AXR with EU4, with 10,000 km on the odometer:

1.) On my slightly downhill home stretch, which I ride with LL mode, the transition from coasting to LL control was happening too early. (--> Slight jolting --> "search function" --> a large number of helpful articles)
2.) AGR.

The following actions were taken:

1.) Der LL-Defaultwert wurde von 32768 (903U/min) auf 32708 geändert. Doch: Statt einem geringeren Verbrauch in der MFA erhöhte sich der Verbrauch von 0,7 l/h auf 0,8 l/h. Man könnte argumentieren, dass die Dieselmenge pro Einspritzung vom Steuergerät angehoben werden muss, um den Motor am drehen zu halten, und dass die Verbrennung dann nicht mehr so effektiv ist. Aber: Das passt nicht so recht mit dem Luftüberschuß beim Diesel zusammen. Erklearning?
Could other AXR drivers please post their LL consumption and LL RPM values (perhaps with a note about what, when, and why was "adapted"?)
I am now using a value of 32750, which corresponds to 882 RPM. At this speed, the mass flow meter (MFA) is showing just 0.7 l/h, not 0.8 l/h.

"Since I want to refrain from any modifications for the time being, I have adjusted the default value of the mass flow controller (MFC) setpoint from 32768 to 33638 (the highest acceptable value)."
Here in the forum, there is only one report that describes this being done with the AXR (apart from hints that "something was adjusted"). However, this report also mentions that the AGR was installed using metal brackets.
Is there a benefit to installing a gasket with a reduced cross-section, as mentioned in a post?
I will be testing some things tomorrow on a closed section of road. If anyone in the forum is interested in specific data, please let me know BEFORE tomorrow morning.

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

"Micha"


Translated on 04-10-2026, 17:59.
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Roger
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Post05-02-2005, 22:04    Subject: Low RPM = High Fuel Consumption Quote

I wouldn't put too much weight on the LL instantaneous consumption displayed on the MFA. Mine (in the ASZ) shows 0.5-0.6 l/h with a cold engine, and usually 0.7, sometimes even 0.8 l/h when the engine is warm. This is without the air conditioning and with the same electrical consumers, as far as possible.
Gruß
Roger

MJ 2018 GTI Performance DLBA

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Translated on 04-10-2026, 18:02.
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