1990 tracker not starting

[Markwalser33]

I've read about everything I can pertaining to my problem. Was running fine then on way to work a couple of weeks ago she cut off on me on the road. I had it towed back to the house. I figured fuel pump. But fuel pump is fine good pressure. So I jumped the gun and shelled out big bucks for an injecter 8 valve throttle body. No luck. I let it sit for about a week and low and behold it started up fine. Drove for 2 days then did the same thing. Checked injecter ohmed out fine but no spray. Checked plug to injecter with noid light did not light up or pulse. Pulled computer opened her up capacitors are fine circuit board is fine. Spark is good. Just wanting some input on which way to go next. Could it be throttle position sensor stopping the computer from sending signal? Or possibly noise suppresser. I went out today and it cranked again but had to pat gas for about 5 minutes Then idled at 3000 to five thousand rpms in park or neutral put in gear would idle at 1000 to 1500 rpms. Drove it around parked it and in park idled at 3000 rpms. Cut it off and back to the same ol same not cranking. No codes on cel only flashes 12. Any help would be appreciated. 
Thanks
Mark walser.