my b18b starts up and idles at 1200-1500 after it begins to warm up it just way donw to about 0 rpm then jumps to about 500 and slowly levels out to about 100RPM what the hell is going on? the olny crazy part about this problem is that it has never stalled (in its current configuration) i have one vacuum hose plged that is sopposed to go to the EGR i do not beleive there is one on my motor but if there is sopposed to be please let me know. thanks in advance

 

plug the egr in the intake. its not possible for a car to idle that low, your tach is probably off.