Seeing as we have some none scoobys here
What car do you have? 1988 Mazda 323 4WD Turbo
What engine is it? 1600 DOHC Turbo
What mods that may affect fuel? its old. very old. and lots.
Whats the transmission, Auto/Manual? 5MT
How many k's do you get to a full tank? 300-320
What fuel do you use? Ultim8