The aim of the present study is to investigate engine performance and the exhaust emissions of a diesel engine using oxidatively stabilized biodiesel. Biodiesel fuel used in the study was prepared from Jatropha curcas oil. Different samples with various metal contaminants, generally available in the metallurgy of the containers are oxidatively stabilized with antioxidant (PY) according to EN 14112. The brake specific fuel consumption (BSFC) of biodiesel fuel with and without antioxidant is more than that of petro-diesel fuel. The BSFC of biodiesel fuel with antioxidants is lesser than that of biodiesel fuel without antioxidants, but no specific trends were detected according to the type of metal content and amount of antioxidants. The combustion characteristics and exhaust emissions in diesel engine were not influenced very much by the addition of antioxidants in biodiesel fuel. Also performance and emission characteristics of unstablized biodiesel and stabilized biodiesel (stabilized for 6 months) are measured with respect to time. (C) 2012 Elsevier Ltd. All rights reserved.