1.9 Mi16 Idle And Mixture Issues

[unariciflocos 49 1 Cars]

I have a freshly rebuilt Mi16 that idles from cold at around 3000 if I connect the Idle control valve and drops to 2000 when up to normal operating temperature. If i remove the IACV then it struggles to hold idle and I need to give it some throttle to keep it from dying. I have black smoke on cold and sounds like it's running on 3 cylinders. The plugs and exhaust are black.

 

The black smoke clears after the engine is up to temp, but the plugs are still black. It's hesitant and jerky for the first few miles and on part throttle, but this does go away after driving a bit. The plugs are still black, but the engine runs nice and pulls well when on more than 25% throttle.

 

The engine is freshly rebuilt, static compression is 11:1(decked block and liners by 0.6 mm). I tried tracing air leaks but couldn't find any, waiting for a spare throttle body from a friend to see if it will improve idle and I'm thinking of winding the AFM coil by one more tooth to lean the mixture out a bit.

 

What are your thoughts on this guys?

 

Thanks,

Andrei