This project deals with the design and implementation of an expert system for car faults diagnosis. The project is motivated by the need to guide car owners and learners motor mechanics in the maintenance and trouble shooting of motor problems without having to resort to presumptions and conjectures. Particularly, it is expected that the proposed design would ensure that car owners have proper assistance in times of crisis and what’s more will save them from the clutches of exploitative roadside mechanics. For this purpose a rule- base artificial intelligence (AI) technique was utilized to obtain theoretical and practical expert system parameters, and then a conceptual expert system was designed. The expert system functioning is based on the database of car faults, symptoms and their correction, which make up its knowledge base. The new system was developed using visual basic 2012 programming language and access database. This language was chosen because of its easy syntax and features for developing windows based application.