That's the thing he/she is meaning, certainly.You mean like in "rip" and "ride"?
- When the letter 'i' is followed by a single consonant and one (of several) vowels, it's pronounced [aï] Ex ripe
- When it's followed by two (or several) consonants, it's pronounced ex differ
I'm sorry to say there are so many exceptions to almost any rule in English pronunciation that the only answer is to consult a dictionary in each case, or listen to native speakers of standard English as much as possible. The exception that immediately came to mind with regard to Pieanne's rule (which is generally true) is the word 'light' and its similar relatives: 'might', 'right' etc. There is also 'mind', 'rind', 'find' [all i's pronounced 'ai'].