What qualifications does an engineer who fixes cars?

Answer 1

Actually mechanics or auto technicians as they are called today repair vehicles. Engineers (in the US as least) are trained to design autos, components, electronics, and other vehicle systems. Technicians usually have a combination of experience and training in auto repair programs at technical colleges or institutes. Dealership mechanics have access to specialty training programs sponsored by the auto companies. Private repair facilities are often owned by former dealership mechanics and increasingly, private shops specialize in vehicles from one or two manufacturers because of the high cost of diagnostic equipment specific to each company. There are several certification programs for mechanics--ASE for example. Graduates have demonstrated knowledge in service procedures. This doesn't necessarily mean you will get a better repair than from a non-certified mechanic but it does suggest the facility takes it's customer responsibilities seriously.