If you go to Pep Boys they will loan you the tool for free. Put down a deposit, get it back. In the end of the tool, that sticks in the spark plug hole. You should see something like a tire valve core. When cranking it should hold pressure in the tool so you will see the compression build up in the gage. Does it sound like the engine is just free spinning when cranking? You could also pull the valve cover and redo the test. This way you can check the valve train over. But it sounds like there is something bad going on inside.

It should look something like this.

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Not this. This is a CLT or compression leek tester.

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