Not a total answer, but I have had the same issue as you, with the same fuel. I am 80% certain the issue went away after running normal diesel for a couple tanks along with diesel clean additive. Switched back to HPR and the problem has come back, bit it is intermittent. Again, can't be 100% certain as I will switch back to normal again for a couple months again, and see if it goes away and doesn't come back. There are many possible causes of this sort of problem, like vacuum leaks or faulty injectors/injection pumps.
Cars from 1983 dont have OBD....that didn't arrive until late 90's