Do I need any other tools to use this tester?

You'll need basic hand tools to remove spark plugs and access the plug holes. The meter and adapters handle the rest — no compression pump or vacuum lines required.

Can this detect which cylinder is leaking?

Yes. You test each cylinder individually by threading the adapter into the plug hole. A pressure reading tells you which cylinder is losing compression and how much.

Does this work on all engines?

Works on any engine you can access the spark plug holes on. Adapter threads are standard — confirm fit before testing on unusual or antique setups.