While talking about it in shout today, I figured I'd make a thread to let others know.
Autozone has a compression tester, the brand is OEM. Do not use this.
@SharksInSpace, @VoodooJef, and myself + @MS3brohanna all used different ones, from different autozones, across the country, around the same time. All 3 of us had part of the gauge get stuck in the head.
Luckily mine was easy to extract. I just had the hose come un-threaded from the extension. just needed a somewhat thin 19mm (iirc) socket to wrench out the extension. Except that isn't necessarily a socket I'd expect everyone to have on hand.
Shark didn't use the silver extension so when some part of the hose blew apart he had to rely on hopes, dreams, and needle nose pliers to get it out . Jef ended up having to pull the valve cover to take care of whatever broke on his. They can all chime in on their specific personal experience if they want.
Furthermore the gauge Brohanna and I used was like 30 psi off cal, so there's another reason to avoid it. But that's a story for another time.
If you need/want to do a compression test, I encourage you to avoid that gauge like 2 valve mustang owners.
Autozone has a compression tester, the brand is OEM. Do not use this.

@SharksInSpace, @VoodooJef, and myself + @MS3brohanna all used different ones, from different autozones, across the country, around the same time. All 3 of us had part of the gauge get stuck in the head.
Luckily mine was easy to extract. I just had the hose come un-threaded from the extension. just needed a somewhat thin 19mm (iirc) socket to wrench out the extension. Except that isn't necessarily a socket I'd expect everyone to have on hand.
Shark didn't use the silver extension so when some part of the hose blew apart he had to rely on hopes, dreams, and needle nose pliers to get it out . Jef ended up having to pull the valve cover to take care of whatever broke on his. They can all chime in on their specific personal experience if they want.
Furthermore the gauge Brohanna and I used was like 30 psi off cal, so there's another reason to avoid it. But that's a story for another time.
If you need/want to do a compression test, I encourage you to avoid that gauge like 2 valve mustang owners.
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