When it's about 40F out, I have to feather the gas when I first start my car or it'll stall. When warm, it idles at only 600rpms. My setup is:

3.5 from an 02 Altima
01 Pathfinder TB
IACV and TB adapters from Stephen Max

My TPS has been adjusted and is correct.

The IACV is located near the fuel rail, nestled in the clusterf*ck of vacuum and coolant lines. The inlet for fresh air into the IM is by the brake booster vacuum source. Total hose between the IACV and inlet is about 18". In the morning, I'm planning on extending the wires to the IACV (all twelve of them...) and relocating it so the tubing between the IACV and inlet is about 2-3".

Before I go through the pain of extending 12 wires, does anyone have any suggestions to help me solve the problem of low idle and cold starts? I have a cammed motor so I'm trying to hit 900rpms when idling.

 

Raise your idle when the car is warm a bit. That should significantly help the cold start problem. You have a pathfinder TB, so turn the screw on the side of the TB near where the cables attach to raise the idle and lock the nut down. Get it around 750-800 at warm temperature, and you shouldn't have the cold start problem anymore.