Tank sensor calibration: Which way to adjust?

Hello everyone,

I want to adjust the fuel tank sensor calibration because, even after filling the tank completely and overfilling it, only 60 liters fit into my 70-liter tank.

I would like to know if I need to increase the value in adjustment channel 30 of the combination unit, i.e., set it to a value greater than 128 or less than 128, so that the fuel gauge doesn't show empty so early.


because I didn't want to only go for walks with the 15 liters that should still be inside.


Trying it out would be the next solution, but maybe someone knows the effect of that setting.


Sure, here's the translation:

'Hi Sulzi'

I just changed it.


If you increase the value, you'll get more liters in the tank, or vice versa. The remaining fuel in the tank will also be displayed.


You can clearly see that on the remaining mileage display.

Great, thanks for the feedback .

Here's another update: After driving my A6 (4B) until it started to sputter and almost run out of fuel, I was able to travel 1024 km.

Previously, with the standard 70-liter tank, the range was only around 840 to 870 kilometers.

So, with the overfilling, it adds about 13 liters, which are now usable.


Sure, here's the translation:

'Hi Sulzi'

hello sulzi,

I drive the same car and I have the same problem .
By how much did you have to increase the value? -> So I can get a rough estimate.

thank you for the information

hello

Today, I made an adjustment to my fuel gauge and read the following values using VAG-COM. The fuel gauge currently shows a quarter full at a mileage of 650 km. The remaining fuel displayed in the measurement block is 15 liters. The standard value for channel 30 for the fuel sensor is 128. I obtained the following values and saved them using coding: The values are always listed first as the fuel sensor value, followed by the remaining liters. 120/13.0 - 123/14.0 - 125/14.5 - 128/15.0 - 130/15.5 - 133/16.5 - 136/17.0. There is approximately a 2-liter discrepancy in the remaining fuel display between the minimum value of 120 and the maximum value of 136. I actually expected a larger discrepancy and a wider adjustment range. A difference of 2 liters plus or minus doesn't really make a significant difference and doesn't really affect the remaining mileage calculation.

Best regards.

hb2000

...Furthermore, in my Golf (manufactured in 2002), it's also the case that it can no longer accurately measure both the first 3 liters and the last 3 liters of fuel (always the same resistance from the fuel sender) - which makes the remaining range estimate quite inaccurate - but perhaps this is only inaccurate in my Golf...

You shouldn't use the last three liters either, as this can cause sediment from the bottom of the tank to be sucked up. The first three liters usually come from topping up the tank; this is the portion that's added after the first time you stop the pump when filling a full tank.

Thank you for the HB2000 measurement.

I have now also done that (I could have also figured out the measurement block 2 myself).

My values:

110 -> 48
120 -> 49
128 -> 50 liters initial value.
130 -> 50
140 -> 52
150 -> 53
160 -> 54

It's strange that values greater/smaller than the minimum value of 120 and the maximum value of 136 are also accepted (I stumbled upon this randomly - I didn't dare to try higher/lower values).

With a remaining range of approximately 50 km, I can fill the tank with about 57 liters. This means that the fuel gauge shows roughly 9/10 of a liter less than the actual amount in my 70-liter tank.

'The average fuel consumption should also be affected by all of this, right? Mine is a bit too high (about 5% higher according to the FIS than the calculated value) -> I've now reduced channel 3 from 100% to 90% -> was that the right approach?'

Thank you for the measurement, Daytrader.

What are those amazing values you can save?

My adaptation range starts at 120 and ends at 136 - the standard value is, of course, 128. I also have a maximum deviation of minus 2 liters to plus 2 liters, which seems to be independent of the actual remaining fuel level in the tank.

You can't break anything by entering higher or lower values. By the way, I don't have channel 3 to adjust. My main concern is the displayed mileage when the fuel warning light first comes on, even though there's still plenty of diesel in the tank.

Best regards.

hb2000

It should be the right direction in channel 3, but a 5% deviation is totally okay...

Okay, here's an additional note for everyone's information:

The adjustment of the consumption value in channel 3 to 90 was a bit excessive – it showed too little. Therefore, it was increased to 95, which seems to fit very well now.

I've also increased channel 30 from its original value of 128 to 150.
Therefore, before filling up completely, the tank held 63/64 liters, and after filling up completely, it held 66 liters.
-> I'll observe this for a while and then, if necessary, increase it a little - let's see what happens.

super

daytrader wrote:

The average consumption should also be influenced by all of this, right? Mine is a little too high (by about ~5%, according to the higher value shown on the FIS compared to the calculated value) -> I've now adjusted channel 3 from 100% to 90% -> was that the right direction?

New adjustment value = Old adjustment value * calculated consumption / old display value

the other way around.

hb2000 wrote:

the other way around

Very informative and concise...