Engine Backfire - Loss of power

I have a 1987 4Runner and noticed some odd fumes like dirty oil that was burning. After routine maintenance I started the engine and found that it was smoking from the exhaust manifold. While trying to locate where the smoke was coming from it backfired, and quite loudly. The engine died as a result for 3 seconds, turned over and ran. After shutting off the engine and following the exhaust pipe I noticed I had no Cat. Converter and the backfire blew out my muffler. I'm not sure if the backfire damaged the fuel injection yet or the intake system, etc. I'm new to the 22REC engine. I recently purchased this vehicle from a private owner with over 220,000 miles on it. I know the exhaust has to be completely replaced but the rest is somewhat confusing. What should I check first?