Oil consumption has been measured for the individual cylinders of a multicylinder automotive engine. The method employed bromine-82 as the indicating isotope and consisted of the extraction of radioactive hydrogen bromide from a known fraction of cylinder exhaust gas. The precision of the method is ± 10%. Oil consumption was measured for the individual cylinders over a speed range 1200-2800 rpm and a load range 18-6 in. intake manifold depression.The oil consumption of the engine determined by the summation of the oil consumption of the individual cylinders agreed reasonably well with the oil consumption measured on the overall engine.Variation in oil consumption between cylinders in the particular engine used was found to be surprisingly large-in some instances a factor of three.Oil-consumption measurements were extended to each bank of the engine as well as the overall engine by the extraction of the radioactive hydrogen bromide from a known fraction of their respective exhausts.