i have a 90 dx that was converted to a mpfi i swapped a d16z6 into it and boosted it ran good till it blew the i got a hold of another hb with a dohc zc in it so i swapped it in it ran good now it randomley will start to idle up to about 1500 rpms and just bounce when its bouncing the lights dim the get bright they dim when idle drops then get bright when the idle gets up. it only does this when the car is warm it idles fine when cold the swap came with a pm6 ecu

 

I A C V

idle air control valve,

might be dirty might be worn out, clean it out with some brake kleen, and run the car till opitmum temp. if erratic idle persits. replace iavc