Nickel and diming

Those intake plenums are junk and it's probably leaking. So much they make a heavy duty aluminum piece that bolts on instead of the oem tin. Could this be the misfire? It's hard to say.

But I have the Hughes plenum kit bolted on a clean, naked intake, never been ran on an engine that I went with a 4bbl FI intake instead. I'll sell it cheap. Pm me if you're interested.