As far as stalling when you let off the pedal. That could be your linkage/bowden cable not being tight enough.

Unplug the electronic idle (ELR) plug on the back of the pump. If your engine kills at idle then you have a mechanical adjustment problem. The ELR maintains your idle electronically. So if it kills without it, you've got linkage etc. to tighten. Most likely it's the bowden cable needs to be tightened. Try that first.

Simple test. Just start the car and unplug that ELR. If it kills you have the mentioned things to adjust.

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