Need to adjust valve train.
Its a 13B renisis engine. No valve train to adjust. the awesome thing about those motors. The rattle is more likely drive train maybe and not engine
Check if your Catalytic Converter is broken, that could be the rattling noise. the pieces get clogged in the exhaust. Be careful ive seen a motor blow because of the massive restriction.
in my case, the engine was decompressed. which ended up having to replace the engine, lucky me it was still under warranty. I had no power, rattling noise and car will die at iddle
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