1. The only way to measure fuel mileage with any accuracy is to pretend the gauge does not exist. Go to a diesel pump on level ground and fill it right up to the brim. Let the foam go down, keep filling until there is literally liquid fuel right at the rim of the tank filler. Where you can see it, and know where that spot is.

Run the car until you get nervous, preferably down close to empty. Refuel at that same pump on that same level ground clean up to the neck again. Then divide the number of miles driven on that tank (write down odometer readings) by the number of gallons you put in the tank.

Repeat at least 3-5x. Then average your mileage. The gauge is inherently useless. I routinely drive 125 miles past when my gauge bottoms out on R.



2. Oil color is a useless measurement on a diesel. There is no "oil getting bad" feature on this car. Only a low oil level indicator light, which is no indication at all of oil change interval. The interval on this car is 5 thousand miles, not 3. Change it at a known time, write it down, repeat every 5k if you use "standard" oil, perhaps 7500 if you use synthetic.

EDIT: I realize now that the odometer isn't working. You'll need it working before any fuel measurement is successful.

__________________


~Michael S.~
Past cars:

1986 300SDL
1987 300SDL
1982 240D
1982 300SD


Current:

1987 300SDL