Why is my fuel economy so bad?
I own a 1992 325is non-vanos motor. I read about people getting well over 500k per tank on these things, yet somehow I just barely break the 500k mark on fumes with super conservative driving.
I replaced my spark plugs, fuel filter, air filter. Nothing made an impact.
I am planning on cleaning the idle sensor soon. I hear that the O2 sensor has a big impact. Please donít tell me about driving style, I know thatís a major factor. I only get 400km/per tank average with normal driving.
How is there such a big discrepancy between cars and fuel mileage? Could compression be playing a factor? Anyone else experience this issue?