AE86 with 4AGE doesn't start

[Dino86]

Hello,

My AE86 with 4AGE Engine doesn't start anymore
The car has been standing for quite a while so I replaced the fuelpump because of rust in the tank.

The engine idles at 300-400RPM only (just not stalling) and only when using almost full throttle. If throttle is released Engine stalls immediatly.
At these RPM I'm not sure it runs on all cylinders but ignition seems OK.
Already I replaced the throttle body and ECU but no effect.

The most strange thing for me is that the Engine does not react to any throttle apply.
(except for stalling at release)
As a next step I plan to check the battery ground and water temperature signal.
Is this a good idea?
After these trials I'm lost....

Can you please help me out?

Thanks a lot