Car acting really weird since last night? Please help!

[catalyst.x]

I recently purchased an S14 SR20DET swapped S13 Hatch. It has been running fine, but last night, i was out and about and right after i shifted into 2nd, the car either backfired, or detonated, or something that was a fairly loud noise.

After that, the car was really sluggish, couldnt really give much more than about 20% throttle and it shook pretty bad. It smelled like it was running really rich, and it sputtered at idle, but stayed running. There was no smoke to speak of, maybe a little but of whiteish smoke out the exhuast.

What could it be? I thought maybe a plug or coilpack, maybe its running on 3 cylinders?

I would GREATLY appreciate any help that can be provided

Thanks!

-Ryan

[catalyst.x]

Charge pipe coupler must not have been tight, it was disconnected under the air filter. Put it back together along w/ new NGK Iridium Plugs and it runs great