2000 Dodge Intrepid wont start

Welcome, if it cranks good but won't start, have a helper crank it, while you check for spark at the plugs, if you have spark everywhere, use a gage and check fuel pressure. You have to start somewhere. Also, you may need to check compression.

Also, has your timing chain ever been replaced? And is your backfire coming from the tailpipe or intake manifold?

I ask this because with your backfire, you definitely have spark and fuel. But if it's coming out of your tailpipe, then it's either an overly rich condition, your ignition timing is way off, or both.

If the backfire is coming from your intake manifold, then you either have an overly rich condition (leaking fuel pressure regulator), your "valve" timing is off, or both.

I know a little about these chrysler V6's, and their timing chains are notorious for stretching, and are a bitch to replace. (Pardon my French)

And if it turns out to be your timing chain, don't bother having it fixed. The rest of your motor will probably be junk as well. And if you shop around, you can find a used motor with 50K miles for about $400 bucks. It'll cost you another $400 or $500 in labor, but you'll spend at least $600 on that timing chain. And the used motor'll run better, last longer and come with a 12-month/12K mile warranty.

And remember to shop around and don't be afraid to tell a mechanic that someone else will do work for cheaper. In this economy, any mechanic will fight for your business.