Hello all. I'm fairly new to the modular 4.6l/ford world in general. I recently bought a 2001 cobra with 800 miles on a freshly rebuilt motor with '03-'04 internals. It currently has a JLT cai, ported DB cast 9 thread heads, and custom tuned. The main issue I'm having with it is cylinders 5-8(driver's side) are running pig rich for no apparent reason, and it's producing a pretty rough idle/smell of raw fuel. I recently switched out the driver's side upstream o2 sensor, which produced no change. I also changed plugs on all 8 cyl.s with same outcome. It is also misfiring in number 5 cyl and producing grey/blue smoke out the driver's side tailpipe at startup. Any ideas as to what's causing these issues? I've already spark-checked the cop in the #5 cyl and it's producing spark. I will also add that I compression tested all 8 cylinders; cylinders 1-4 were between 201 psi and 206 psi, while cylinders 5-8 were between 230 psi and 236 psi. I appreciate any help/answers to this nightmare.
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