KA stalls upon decceleration/sketchy idle issues

[Dr.Noisewater]

So I own a 93 Nissan 240sx Base Model with the complety stock KA24DE. I just rebuilt the motor and dropped it in a few days ago. She has a huge exhaust leak before and after the cat which I'm fixing soon. However my biggest problem is the car will not hold idle well and upon decceleration she has a tendancy to stall out. I have a new fuel filter and I did run it a bit with old bad gas if that might cause these issues. I really need to get this car going as it is my only car and I need to get to work! Thanks for all the time and help!!

[Dr.Noisewater]

Update: I just discovered that when I was setting the timing I was supposed to unplug the TPS. Would having my engine off timing maybe cause these idle issues???

[OutToWinPAHC]

Fix the exhaust leaks, Check for vacuum leaks, check the plugs, set the TPC, and clean the intake and IAC and check the timing. Maybe try pulling the injectors and soaking the tips in sea-foam and replace the O-rings.