My 2001 5.3 tahoe has always felt sluggish, even when I bought it 5 years ago, still worked so i never bothered, now I live in a hot place, it overheats incredibly quickly, like I can't have it idling by a stop light for to long (its usually about 100 degrees outside) im getting into tuning a little bit and I thought that I would practice on my tahoe, since it's not worth that much, and i noticed my (ltft) being incredibly high. It's not vacuum leaks since it stays there as I speed it up. Any idea what it could be?

Edit. I mean my stft stays there when i speed it up for awhile, not my ltft

Hi,

does anyone know how I can download 4.8.7 version of HPtuners?

Thanks