The black box is the engine computer / ECU / HFM_SFI box. Before you get another box, be sure the wires from the coil to ECU plug are not shorted to ground / shorted to power. Wiring harnesses circa 92 to 95 had poor insulation that would crumble. You will need a wiring diagram to find out what pins on the ECU match to the coils.

I'm pretty sure the calibration chip is removable so swap it to your new unit if you make a change.

If the wiring is good, open the ECU and have a look. Follow the coil pins into the box and to a power transistor. It is likely this transistor is bad and changing it might be possible.

Have a look at car-part.com , it is a online salvage yard inventory system.


From left to right in your pics.

GM General Module ( this is a relay box for misc functions . )

016 545 62 32 HFM-SFI ECU

CARB Diagnostic module

HGS ( this might be transmission cold up shift delay, first gear start, kickdown )

ASR Acceleration Skid Reduction ( also controls ABS function )

E-GAS Operates the electronic throttle assist