My question is really more rhetorical than asking for a real reason that both the iPhone 4 and iPhone X are shown as being...

Greetings. I just replaced an expanding battery in an iPhone X and want to test the screen after replacing, especially...

Aside from what has been talked about above, you might want to consider a clogged fuel filter. If it hasn't been changed, and is relatively easy to access, it's a good maintenance item to replace anyway at 95K miles, IMO. A fuel starved engine will run lean, and therefore will run hotter, so you might smell that this is happening, as you sort of described. It will also hiccup a bit. If it's spark related, then it could very well be the CKP, aka the crank position sensor. That said, these are usually a real bear to get to for the unseasoned mechanic in particular. With many cars easiest access to potentially failed part can be a prime determinant in how one goes about fixing things. Good luck with your Mazda.

I've answered my own "mostly rhetorical" question by replacing the battery in my old iPhone 4. There is no comparison in the difficulty levels between the two. The X was a royal pain, and had more things to go wrong while doing the replacement than the old 4. If one can't replace the battery in an iPhone 4, they probably have someone pouring their breakfast cereal for them as well. ;-) Cheers.

I realize that this question was from 9 months ago, but I figured I'd add a related comment. After being pretty careful at replacing the battery in my iphone X, and subsequently replacing my display, I noticed that one of the ground doohickeys got a bit scrunched up. I looked at it under a stereo microscope and saw that these things are made out of some sort of woven metallic belting that can be scrunched without being torn, etc. I figured that with only one being a bit damaged, it had a good chance of being OK. Of course, I don't really know what their function is so it was a bit of a leap of faith. After reassembling, everything seems to be working fine. Sometimes such leaps don't end up with a face-plant. Oh, what I did notice is that this part isn't particularly easy to find. I see used ones that look way worse than mine being sold on the big auction site, but not really anywhere else. This seems odd considering they are rather easily damaged if they get brushed against something. One might deduce that...