i bought a second hand yrv on a y reg last year a few weeks into owning it the engine warning light came on i took it into the garage and they fixed it for about a day!! it came back on they said somthing about a sensor with a top case and a bottom case and they changed the wrong half, and they are wating to find a new dealer for parts for my yrv so cant fix it at the moment,anyway today i noticed that there was some white stuff on the oil cap could this have to do with the engine warning ligh the car drives fine,