Idle Problem..Surging? ISC Maybe?

[BoostedinSoFla]

So I started my car up today after it's been sitting for a while and the idle was at or around 1800 RPM's. It was just reving continuously at that RPM level. I tried to adjust the BISS screw so I turned it to the left and the more I turned it the more the idle went down but just a little though; and then it started to surge. Now whenever I turned it back to the right it went back up and continued to surge.

So now the CEL came on and it surges continuously. I also noticed that when I turned the AC on the surging went away and the idle dropped down to about 950-1000 RPM's (right where I want it) but the CEL is still on. It drives fine but the surging and high idle is killing me whenever I come to or about to come to a complete stop.

It's funny cause I just installed a used ISC about 2 months ago so I don't know what else it could be.

 

[romeen]

Have you checked to see what code the ECU is throwing? Do a resistance test on the IAC as outlined in vfaq. Are you sure the idle went down when you turned the BISS counterclockwise? That should cause the idle to go up and turning it clockwise should decrease the idle.

Here you go: http://www.vfaq.com/mods/wayback/BradBauer/engine/surge.html

Scroll to bottom for IAC testing.

 

[BoostedinSoFla]

Have you checked to see what code the ECU is throwing?

No, the car's not registered so I can't drive it to Advance to have them scan it for me but the CEL was never on before this so I'm assuming it's on because of this problem.

Do a resistance test on the IAC as outlined in vfaq.

Do you mind providing me with the link?

Are you sure the idle went down when you turned the BISS counterclockwise? That should cause the idle to go up and turning it clockwise should decrease the idle.

Now that I think of it I explained it wrong. Yeah, the idle actually went up when I turned the BISS screw counter-clockwise and now it's turned all the way clockwise but still surges and idles high.

 

[BoostedinSoFla]

Here you go: http://www.vfaq.com/mods/wayback/BradBauer/engine/surge.html

Scroll to bottom for IAC testing.

Thanks Romeen. I'll read up on that now.

Does anybody else have any other suggestions?