My 87 fc turbo will not idle
 

So recently I've been working on my fc 1987 turbo and I finnaly got It to start after a few weeks I bought the car with an engine and a transmission (I'm 16 )and my dads a mechanic so he would work and I had my own bay to work on and I mounted all my parts and then I ran out of time and I just left what was left for my dad to work on the side so skip a few weeks in advance car starts but the idle wont hold I have to rev to keep the car alive I've driven it and I lose power and car dies because of idle problem It has held for a few seccond it holds 1500 and dies in the matter of secconds I'm new to rx7 but it was a great learning experince and I just need someone's help with this issue to be on the road ps my throttle sensor is connected