I have a 2018 Ducato and its the 9th Fiat ducato we have owned
The first fill from new only 50 ltrs went in so
Checked the specs it left the factory with a 90 ltr tank. They cant find the problem but it is showing up all over the world on 2018/19 models
Below is what the agents have undertaken over 5 visits and still on going
They checked the sender was reading but I had to return so they could drain the tank and prove its capacity
Drained the tank saying at empty there was 30ltrs remaining. They said they re-calibrated the gauge. I then took a long trip but at each fill it was only 49lts to 52ltrs and the distance remaining only showed 600klm each fill
Returned with the vehicle and they 'checked the sender was correct' but ordered a new 90ltr sender and I was to return.
I managed to arrive at the dealership with the fuel warning light on so they proceeded to change the sender.
When I went to drive up the van the fuel warning light was still on. Their answer was to reset the speedo and drive it so it could correct itself.
I drove it down to a service station and filled it with 52 lts and 520klm distance remained then return to the dealers.
I took it back to my yard where I had a new customers van, so got under and compared the tanks. The molding numbers same and physical dimensions were the same as near as you can measure an oval tank.
I have compared several tanks and even swapped the speedo head with my other 2017 van. The gauge showed the same level but the mileage of the other van was showing.
My other van and several friends have all noted the fills and they take average of 80 ltrs if empty and 900klm as a distance remaining at filling
It is very unreliable for planning fuel filling as NZ the diesel stops are far and wide.
Just the last trip entering the motorways to Auckland 50klm from home the distance remaining was 180klm but at the start of the system there is a hill 1klm long, at the top of the hill the distance remaining dropped to 72klm this would have seen me on the roadside without fuel so had to make a side trip to find a station.
somewhere on this site it said the "The Fuel tank capacity is set by parameter in the ECU".
Any suggestions?