So... I am at my wits end with this issue.

When braking or when driving DOWN hill, the engine stalls out completely. It will start back up without an issue once the car is at a dead stop or if I pop the clutch, but when popping the clutch it will stutter horribly before picking back up to normal RPM.

I have replaced the IACV, the fuel filter, checked the fuel pump (pain in the ***...) have checked timing, replaced plugs and wires, tried with different levels of fuel in the tank... No changes.

I even tested by putting the car in neutral and revving the motor up a bit while braking and it still cuts off no matter how much gas I give it. It seems to only be when force is pushed toward the front of the vehicle (i.e. when braking or driving in reverse or on a declining hill.)

Someone please help! The ECU is not throwing ANY codes...

 

Sounds like a fuel issue. I had the same thing happen to me, but it was the fuel filter. Check the fuel pressure regulator, especially the vacuum hose that is connected to it.