So I have owned my 92 fd rx7 for about a month now and I have pulled the motor and found a loose sensor, a broken wire, a clip and some type of valve off the turbo y pipe. The sensor i am talking about is right above the trailing spark plug on 1st rotor. I have no idea were or what they are for. Here are some pictures I took. Any info is greatly appreciated thank you.

 

The gray connector in the first two or three pictures is for the Air Pump, which was removed from your car.

The second loose wire I'm not sure. Possibly the coolant level sensor "disconnect' as seen below (not my picture). The coolant level sensor is the black plug on the front of the t-stat housing. Try following the wire back from that and see where it goes.