This book did very well in helping me understand how an engine really works. Jack Erjavec went into deep detail on the entire engine process. The diagrams and step by step instrutions work well together, as well as helping the reader understand what to do, better than other books I've read. The book was made in 1986, so it is basically out of date. Comparing the cars in the 1980's and the cars of today, it is probably not a good idea to use this book to fix a present day car.