Just a quick one, could not having the intake tube on cause a backfire? It's got a new opti, new plugs, new MSD wires. Just hadn't gotten around to reattaching the intake tubes yet, but it minority backfired (I think) twice so far. It was low on gas at the time too if that helps

 

I would think the low fuel would be more of a concern....an intermittant fuel supply can cause the backfire but running the tank dry can overheat the fuel pump and cause premature failure....

There shouldn't be much concern not having the intake ducting in place on a speed density car beyond allowing dirty air into the engine.....

 

The pump was just replaced as well. The only thing fuel-wise that isn't new is the injectors and regulators actually.

 

Easy enough to figure out. Put some fuel in it, check the pressure at idle and driving and eliminate fuel delivery as an issue.

Since you just changed Ll the ignition stuff, recheck the wiring and routing....

 

Did you have the "minority(??) backfire" problem before you replaced the parts you listed, or did the problem occur AFTER you replaced the parts.

 

No, the "minor" (stupid iPhone autocorrect ) backfire is new, but its only new since replacing the wires, AC compressor, ps pump, and reinstalling the egr tube. I double checked the wires, nothing crossed, and it hasn't done it since I put gas in it. I'm going to the the FPR and injectors next. I think there is a minor exhaust leak coming from the egr tube, but I don't know if its on the header or the intake yet