hi.I have an issue with my car withbit struggling to start first thing in the morning...every start after that it's fine but that first one or a cold start it cranks for 5secs and then starts with a load of smoke & smell from exhausts I've changed the battery and the glow plugs. thinking it may be injectors? but would like a scan doing to be sure?can you help with and would it show up faulty injectors? thanks