Mine does that too, especially right when I start it up. I've never felt like it was going to stall, though. Usually I'm between 1500 top and down to 800. My heater is running, so that may be the cause? It's getting chilly here in WI ha ha.

 

Okay so its doing this with the heat off.

It did this on the stock throttle body as well as my ported 65mm one that's in there now. So I don't think it has anything to do with any settings or the biss

I'm running gsc s1 cams, but its not them because it didn't do this for the longest time I had them in my car and I know my timing and tensioner are fine. Car was also tuned by chad at CBRD and ran perfect for the longest time when he was done with it. So I highly doubt anything is wrong with the tune

And yes sometimes the car idle does get real low and feels like it might stall, usually as I push the clutch in coming to a stoplight or something.

Is there a way to check the ics? Not just assume it went bad on me?

 

When it starts to get cold out, our cars rev higher when you start up "high rev" to warm up the engine faster.

If your car has a fluctuating rev then you need to check your TPS, throttle position sensor.