Actually measuring the fuel level sender resistance is used in skoda economy run to measure actual fuel consumptions and results of the fuel economy race.
What they did was:
- Start with empty tank and measure the resistance value with VAG com etc
- add 1 liter of petrol or diesel and check value. You can use which liter value but less volume more accuracy. First check which is minimum which changes the value...
- Repeat the procedure until the value does not change and you have created a accurate way to measure the used fuel in a fuel economy race or just for your own fun.
- In their races all cars are the same model and when you come to race tank cannot be full. They know it from the resistance value...
- When you finish the race you just need to read the resistance value and fill the tank with that amount of fuel the resistance value suggests from the chart you generated. If the value becomes the same you have your exact fuel value burned. Ofcourse you need to be very precise with positioning of the car when you do your fillups in a race and for that there are ways to do it accurately.
This way you dont have to build a super long race of 400+ km to see which is best and fillup data is usually more accurate than with regular fillup methods as you can check the results from that resistance value.
Now you just have to measure that resistance value in same place like some level part of your regular route if you use this method. More precise data means less km or miles drived in testing purposes. you just need to test which is the minimum amount of added fuel the resistance value changes.
From that you can calculate the distance you have to drive to see results that are pretty reliable.
Have fun with this
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