This BMW E39 535i has a V8 petrol engine and an LPG system. During the inspection, the gas injectors were found to be working poorly, and the engine ran unevenly on LPG. All eight injectors were replaced, after which the engine ran more smoothly.

The car was then tested on the dyno using both petrol and LPG. It produced 260 hp and 356 Nm on petrol, compared with 251 hp and 357 Nm on LPG. In this run, the power difference was 9 hp, while the torque readings were almost identical.

These figures apply to this particular car and LPG setup. Injector and reducer condition, along with system calibration, can affect how an engine performs on gas. The dyno runs and graphs can be viewed in the video.