There's two common causes. One is a cracked flex plate. More common is a broken timing belt. You have an engine problem and you didn't bother to list the engine size, so I can't look up if it's an "interference" engine. If it is, a broken timing belt will result in bent valves and no compression. The engine will spin very freely.
To determine if one of these are the cause, watch the crankshaft pulley and / or serpentine belt to see if they turn when a helper cranks the engine. If they don't turn, suspect the flex plate.
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Tuesday, September 15th, 2015 AT 5:29 PM