i was driving my car down the road and made a huge back fire and turned off and now wont start what could it be the opti?

 

Im sure it "could be the opti" but you should at least perform some basic checks before condeming a 400 buck part. A question like that is unanswerable without a lot more information. Was the car doing anything strange before this happend? Does it have fuel pressure? How many miles are on the car? What year is the car in question? Does the car have spark or injector pulse? ect ect... Give us something to work with and we might be able to help you.