'92 Grand Am won't start

1992 Grand Am won't start. 4 cyl ohc engine shakes like crazy when it seems to want to start but it won't catch. Fuel pressure good. Checked engine fault codes but 12 code kept flashing and wouldn't stop. Any help would be greatly appreciated.

Been along time since i've ran the codes on a pre - OB2 car, but I was able to find a reference, http://www.gnttype.org/maint/malf.html , seems the computer always starts out with 12, 12, 12, then the code number you want , 12, 12, 12. all 12 means is your computer diagnostics is functioning correctly, if all you get is the (6) 12 's then an error code isn't coming up. Unless I misread something, its been a long time!

Are you getting spark to go with the fuel? I have a 95 quad 4, and im not positive the differences, but if im not getting spark on any of the cylinders, the first place I would look is the Crank Position Sensor, then Ignition Control Module, if im getting spark on two cylinders the coil, if im getting spark on 3 cylinders id look at the coil housing. Hope this helps you track down the problem, be sure to let us know what the problem was, and any other symptoms you discover along the way.