96, 2.2L sunfire

hey guys, sorry for making it my first post but after leafing through a couple dozen pages of threads couldnt find anything... so heres my question

started happening about a month ago, whenever i go to start up my car it makes a horrible crunching/grinding noise. been looking around and googling it but my search so far has been in vain... any ideas? or someplace to start looking?


thanks,
john

also,

is it difficult to change the ingition?