Modern car engine management is nowadays almost totally computer based which means that should a problem occur a fault code is logged in the cars computer.
Sometimes this just a warning, sometimes it identifies a temporary problem and other times it indicates a major problem. Often in the case of warnings and temporary problems it may be possible to reset the system but in the case of major problems the fault has to be located and rectified.
We have invested in a considerable amount of specialist diagnostic equipment to enable these problems to be both diagnosed and rectified as appropriate. We also have some of the very earliest pieces of diagnostic equipment kept in working order as often modern equipment cannot communicate with the systems on earlier cars.