Spark plugs that haven't been changed for a long time can become one with the cylinder head. Fortunately, it's possible to repair damaged threads instead of scrapping the head. (Photograph by Chris ...

If you find that a bumpy road broke off the end of one of your old spark plugs, you should probably call a tow truck. Just don't try to MacGyver your car like I did. The last time I got my car out of ...