It sounds more like the timing chain has jumped a tooth or two. If it was a burnt valve or head gasket it would not affect all cylinders the same. Here is how to check the timing marks to confirm the failure. Also, was the engine making noise before the issue of not starting? You can check the timing marks by removing the valve cover. Here is how you can change the timing chain out in the diagrams below. It also shows how to change the timing marks.
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Saturday, June 25th, 2022 AT 5:38 PM