Need a little help with this one. My car has a constant backfire on the drivers side bank only. I have no clue why. things I've replaced thus far to narrow it down.

MAF
plugs
wires
O2's
fuel injectors

When I first crank it up it dosent do it right away. Once the car is up to temp it starts to back fire. it seems like it's spiting fuel into the the pipe and then igniteing. It does it at idel in park, under load, gets worse as you step on the gas. When you go full throttle it bogs really bad. I tried turning down the fuel pressure untill it almost stalled. Got a bit better but didn't help. It's also knocking pretty bad too. I was told it may be an exhaust leak but I'm not sure yet. I don't hear it. It may be at the collector but I havn't checked yet. Any thoughts are greatly appreciated.

Shaun,
Throw a vacuum gauge on it and verify that you don't have a valve hanging up or something. I've seen a bad lifter, valve spring etc do this. If the vacuum is steady then I'd check out the ignition secondary and narrow it down to one cylinder.
Unfortunately, you also might want to do a compression check too.

Thanks Kev. Not what I wanted to hear but I'll give it a shot. See what I come up with.

Could it possibly be a mis-interprited spark knock??

Kinda sounds like a possible burned valve to me........Or sticking or bent (stuck) or something along those lines!