Idle IAC issues

[Calabresemic]

Hello everyone,

I've been trying to dial in my tune and I've ended up with this random IAC movement when the engine warms up.

LQ9 with cam, headers, long tubes, and LS6 intake manifold.

I attached my tune and a log with the issues. Cold start (from 64 to 149 degrees) it's perfectly fine. Slight movement but it's cammed so I expect it to not sit still. Then at 7:40 it just goes crazy and starts flipping back and forth. I don't see anything that would point to what is causing the issue. I've searched a lot but haven't found anything that would cause it. Nothing changes at 150 degrees and nothing seems to really point to adaptive idle causing the issue since it's not even triggered until 176. Any help would be greatly appreciated.

[curiousg7]

Try raising idle to 800, maybe it doesn't like going from 875 to 775 immediately then down to 750 commanded. Also does the cam have a lot of overlap? Your injection timing is later.

[Calabresemic]

Curiousg7,

I put in the idle rpm table from a 99 Camaro to test that theory. I also put the injector data in it from this forum post(same injectors): https://forum.hptuners.com/showthrea...l=1#post394202.

I lost the cam card but here are the advertised specs for the cam, it's a Tick Performance Street Heat Stage 2. 231/235 | .625”/.605” | LSA113+3

I had that data in it before and it was running fine but once this started it reverted basically everything in it back to what I pulled off the ECU from my tuner. I'll go let it warm up and log what happens and post it up.

[Calabresemic]

Here's the log of what happened. Not really any better.