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I would start by checking the engine oil level. Rattling may be a sign of the timing being off, possibly because of the variable intake timing control. This uses oil pressure to work properly, so low oil can cause this type of problem.
Without codes it's difficult to know for sure, but it sounds like this or the timing belt may be the issue here. Also, if you have the car home safely, I would suggest you do not drive it if the oil is full. If the timing belt is having an issue, this will damage the valves.
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