have you checked for codes? you can do a search here but i'm pretty sure you want to short pins A and B in the diagnostic connector and see if your check engine light flashes any codes. post up what it flashes. you should get a "12" or 1 flash then 2 and then any actual error codes will flash.
also, i know the LT1 has a "reduced rpm" mode that only turns on half of the injectors as a protection mode. i dont know for sure what conditions will activate that mode though, jimn will probably be your best answer on that.
you can check the resistance of the coolant temp sensor at the ECM and see what it reads at the time of the problem. ohm it out at pins J1-2 and J1-29 and post up what you had, i have a chart for that. max on the chart is 212 degrees which is 177 ohms, lowest i'd expect you to see would be about 60 degrees which should be 4450 ohms.
1997 Prostar 205, LT1 powerslot
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