I have a 1990 miata that when you start it up, you dont dare touch the throttle or it will die. then the only way to start it is to pull start. If it does start, you can give it gas only after you hear the change in idle. The power it should have is just lacking. Has anyone else encountered this mind boggling problem? If any suggestions I am listening.

 

I have a similar issue that I am going to be looking at tomorrow. Right now I am guessing:
(1) Vaccum leak(s)
-Going to check all hoses and recommended checks from Haynes

(2) Fuel system problem (since it started RIGHT AFTER a fill up from empty)
- Check the fuel cap
- Check the fuel filter
- Check the fuel injectors
- Check the Throtle Position Sensor

As this is an old post... hopefully you were able to resolve the issue?