First, it is likely a percentage off between the two, and in a car with better fuel economy the raw MPG number difference will be larger. But that seems too large to explain this completely.

It could be that the software was written for gasoline. The program is tracking injector pulse width on one of the cylinders to track the amount of fuel being used. The difference in viscosity between diesel and gasoline means a different amount of fuel gets injected. If the computer thinks it is injecting a the wrong fuel, there can be issues.

I also see your fill ups are a bit erratic in fuel economy. Try recording the dash display results in the notes, and we might be able to see a trend on when it is off the most.

As to VW shenaigans, isn't the 1.6 only of the cheater engines there? The dash display being off could be an artifact of the cheat code. Not necessarily delibrate on VW's part.

I actually read that 1.6 TDI in particular needs not only a software update, but the injectors need swapping too. Is it possible one or the other has not been? Has the car had the recall?

I'm finding a bit of a discrepancy in my fuel usage results between what it shows on the car and the Fuelly website. After a trip up north on the weekend the numbers showing on my dash was 7.6 ltrs per 100 kms. In this site (https://pacificwebsites.com/Convert_L...per_Gallon.htm ) it shows that 7.6 per 100 translates to 37 mls per gallon. Yet, Fuelly shows it at 26.7 mls per gallon. Am I doing something wrong or is there a problem with the cars results.???


2015 Chrysler 200 Limited - Build Date 03/15 - Vivid Blue - Black Cloth Interior - 3.6L 6cy -

You might need to check your settings, there is US MPG and UK mpg, they are different measurements.

That chart shows the imperial gallon, not the US gallon which is smaller and might be what Fuelly is calculating for you.