I am having a idle issue with my 99z (ls1). The car will idle high and jump around alot. When I go wot and release the pedal the car will surge and idle will sick to about 2,000. I did replace iac but the idle still jumps around. My next thought was imaybe the tune I have been working on caused this issue. Since it does it worse when I turn on the heat/air. This forumn has helped me before so I am hoping someone can shed some light on this problem for me.
Thanks, Jake
