Burnt valves means it's been running VERY lean - don't thrash it until you have it diagnosed properly.

FYI error codes:
22 Knock sensor
23 Mass air flow sensor
53 Fuel Pump or Circuit

I'd say you MAF died - you boosted it and it knocked itself to death. Swapping the MAF won't fix it because the damage was done the first time you hit boost when it was running sick.

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