Hello!
I went and refueled the 116 for the second time, on Saturday night. Partially because I believe that full tanks are happy tanks and partially because I've found that this is the best way that I can most accurately calculate my fuel economy, I'm in the habit of filling the fuel tank right up to the brim. On the 123, this can take me upwards of a half hour, because diesel fuel tends to foam up and I have to wait for the foam to die down. The presence of the foam means that, if you simply fill up until the pump clicks off, you won't get the fuel up to the same level every time (this is why one of my reasons for doing this is to calculate the fuel mileage accurately). Also, getting the fuel all the way up to the top of the fillneck means getting an extra 2 to 3 gallons in the tank as compared to stopping when the pump shuts off.
So, I went and fueled up the 116 like this...and came across a surprise. With every other diesel I've ever owned, once you get the fuel to the top of the fillneck, the tank would then "burp", the fuel level would go back down, and repeat the process maybe 7 or 8 times. The 116 was different. Once I got the fuel up to the top of the fillneck and the standard burping finished, the fuel level would SLOWLY surge down until the level was just barely visible...and it kept on doing this, even after topping it off countless times over the course of almost an hour. Fortunately, it was late at night so there wasn't a wait for my pump...
I at first assumed that the tank vent was plugged or something on those lines, and it was even more difficult than normal for air to get out of the tank. Then I saw that I had pumped 22 gallons into the tank.
I was under the impression that the 116 had a 21 gallon tank, and the fuel gauge at least SEEMS to be reading accurately...it isn't swinging wildly, and the car was driving like there was still ample fuel in the tank, and I fueled up at 1/4 tank remaining (483.3 miles on the trip odometer). BTW, the pump first clicked off at 18 gallons.
So...is the 116's fuel tank a weird shape, or could the fuel have been going somewhere else? I actually checked the trunk and the rear footwells (as well as under the car) to make sure that fuel wasn't overflowing into somewhere that I didn't expect.
I know this is somewhat odd, but any thoughts would be greatly appreciated...
Thanks in advance
