11/28/2005, 2:21 p.m. ET
By ELISABETH WALDON
The Associated Press

CARSON CITY, Mich. (AP) — The exhaust from most diesel engines smells like diesel.

Justin Keiffer’s 1984 Volkswagen Rabbit smells like doughnuts. A 2002 Carson City-Crystal High School graduate, Keiffer, 21, first became interested in biodiesel fuel when writing a paper on the subject in teacher Mike Steere’s high school class.

Now a senior at Kettering University in Flint, where he is majoring in mechanical engineering, Keiffer is immersed in the study of biodiesel fuel. He purchased a 1982 Volkswagen Rabbit pickup truck for $100 and later the ‘84 maroon car for about the same price on eBay. Keiffer began using vegetable oil free thanks to the Carson Village Market bakery in Carson City in March and says he has saved more than $1,600 in fuel costs since then.