There is a chance on some moddels that they will not start when an oil sensor fault appears, but this will most likely cause a bog drop in power to protect the engine. I am not sure what the smoke in the cambelt cover is. If the engine turns over when turning the key and the engine does not take and seems to almost backfire it could be your air flow meter above the air filter box, unplug it and try starting it that way, if it starts it most likely will not idol, or idol rough, that is the onlt thought that comes to mind. Check what happened to ot from the prevous owner, maybe that can add more light on the problem. Good luck.