1989 cavalier has no spark
Which engine do you have in it? Is this all the time (hot/cold engine)?
Note: in these early year efi chevys the computer was not very reliable, four cyl models especially,v-6 3.1 used a slightly more reliable model ecm v-6 scan the system, do you have communication, if yes needs a ignition module,under coil packs under front exaust manifold. Four cyl I believe it has a distributor. Follow first step,scan. If spark is present in a cold start,and quits warm,pick up in distributor. If spark is just not present it needs a module as well. No communication. Ecm is junk,when replacing ecm save prom chip