No help?

I'm not sure if it's misfiring or not, it seems like it but runs fine over 700 rpms. Its a hesitation or stutter maybe a misfire but the pcm is not picking it up. In gear at an idle with the a/c on it flutters from 600 down into the high 400's and my lights will dim in tune with it.

I wasn't saying the tune caused this problem. I'm wanting to know if the data logging process of the tuner will show or help find the problem or if someone would take a look at the log I made on the tuner. I understand a misfire would throw a check engine light, I have none. Is that true?

2007.5 Chevrolet Silverado 5.3. No engine codes or check engine light but my truck is missing/hesitating at low rpm and idle. have had intune programmer on it for a few years. please help. will the data log catch the problem?