fried?

[INJEN78]

just got my 91 crx si running good,its an obd0 b18a1,but when i start it up it idles at 2 grand and slowl drops to 800(thats fine)
but thats on a pm6,now,when i run the pr4 it revs to 2500 then slowly drops to 1000 and then when it hits 1000 it jumps to 1500 then to 800 back up,back down,etc.
so is my ecu fried?

idles perfect with the pm6,but surges with the pr4??
i was going to chip the pr4,but if its junk,theres no point

 

[efhondakid]

Colant level good? Unplug the IACV and see if that fixes the surge.

 

[INJEN78]

yep coolant is fin,it only does it with the pr4 though.
im gonna bleed it 2mrrw,and check the iacv