In the present competitive and demanding business markets, manufacturing industries need to improve their strength and must concentrate on their process flows by assigning the task resources carefully to improve productivity. It also focuses on continuous improvements with the total involvement of all employees with optimum utilisation of man power and machine by reducing idle time and lead time. They also provide the application for variety of tools and strategies which can help in identification of waste reduction or elimination of waste, lowering the product cost, reducing human effort and minimising product manufacturing time. In the current competitive business era, an industry unable to sustain in the global business without implementing the computer integrated manufacturing in the manufacturing environment. In order to overcome, a computer-based lean audit methodology is to be implemented in the production environment for improving the production characteristics like quality, reduce wastage and reduce non-value-added activity. This article presents a case study carried out in a foundry division of an auto parts manufacturing industry which results in improved system performance. At first, the two lean tools namely Kobetsu-Kaizen and value stream map are implemented for improvement and also these findings are integrated with computer-based lean audit system for improving the production performances or measuring the lean characteristics. The implementation shows improved performance in terms of average core rejections, sand leakage, air lock problem, reduced lead time, non-value-added time, set-up time and number of operators required. © 2017 Informa UK Limited, trading as Taylor & Francis Group.