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Check for vacuum leaks. If you disconnected any during the upper intake R&R, you may have a leak. It can throw codes like these. Live data scanner is the only sure way to check the condition of your O2 sensors.
I will do vacuum test. If there are no air leaks, do 174 & 1174 indicate front O2 sensors need replacement??
Live data scanner is the only sure way to check the condition of your O2 sensors. With one of these, you check the output voltage of each sensor while the engine is running. Anything else is a guess.