Help Please could someone tell me why my 86 rx7 is surging in 1st gear everytime i give it a little gas the car surges foward then slows then surges foward again, if i adjust what i believe to be the fast idle control [which is on the throttle body has a spring around the screw and i think is connected in some way to the metering oil pump connecting rod ] the surge is suppressed but the idle then becomes unstable and i can`t seem to find a happy medium.Is that screw not the fast idle control and if it is why does it make the car surge.It almost seems like I have adjusted the clutch which of course i have not. thank you