As some of you know, I'm in the process of finishing my 1988 900 SPG. Well, we got it all together, but now it wont start. It has spark, and the fuel pump works, but the injectors arent opening. We tried different Jetronic boxes in it, and tested the original box in another car, and it worked in the other car. The box is recieving the signal from the distributor, and the box is sending the signal to the injectors, but the injectors arent recieving anything. So we've basically narrowed it down to between the ECU and the injectors. Also, the tachometer doesnt move when trying to start it.