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Check for vacuum leaks, the pump going from the air box to turbo is common to crack and take in unmetered air. Also check the pipes going to the intercooler.
Use a scan tool to check fuel trims at idle and let me know what you have.
Does it idle high?
Sorry its "pipe" seems the auto correct changed the word to pump.
Disconnect coil packs one at a time while the engine is running to see which cylinders are missing. If the engine does not change you found the bad cylinder. If it stalls or idles more rough you know that cylinder is firing.