Abstract:

 A fuel consumption consistency problem was analyzed for a front-engine front-drive (FF) vehicle with a poor fuel consumption (FC) consistency to meet the four-stage fuel consumption limit and corporate average fuel consumption (CAFC). A vehicle energy flow method was used to simulate and test an idle fuel consumption and a subsystem interchange to eliminate some influencing factors such as engine, gearbox and exhaust system. The source of fuel consumption differences was focused on the electrical system through disconnected motor tests. Generator efficiency was tested to eliminate the impact of generators on power consumption. The results show that electrical power consumption accounts for 34%, and battery charging power consumption accounts for 66%. Therefore, the difference in power consumption comes from electrical appliances and batteries, and the initial charge of battery is the major factor. 

Key words: front-engine front-drive (FF) vehicles , fuel consumption (FC) ,  energy flow , generators ,  batterys