I had my 7 battery replaced by an Apple Authorized dealer. Around 2 weeks after the taptic engine started to make a !&&* of a noise when it was activated (sounded as if it was loose)… then 1 month after that… it stopped working completely. fast forward 8-9 months later, the battery they had replaced just wasn’t holding its charge anymore (phone was spending more time plugged in charging and depleting very quickly = full charge lasted about 1-2 hours). Having bought the ifixit battery and have gotten as far as this step, I could see that all three of the 1.6mm screws were just floating around in the compartment and the taptic engine was just being held on via it’s ribbon lead. WTF?! Screws aren’t stripped and I managed to fix it in again. Why would these screws be floating around like this??

The barometric vent seems to have some foam cushioning towards the bottom of the case? does this get damaged via removal I wonder?

Worked for me. B&ttclench when the adhesive strips went on, but got there and battery placed fine. Good instructions. thanks. Just hope it all powers on when its all re-assembled again. ;)