What kind of noise? Check the obvious first ensure the engine oil and coolant level are full. Is the noise a knock, or a noise that increases with engine RPM, can you determine if it at engine speed or half engine speed?
Oerhaps the noise is from the outside of the engine something driven by a fan belt, you may have to remove the fan belts to isolate the noise identifying that it may be an air conditioning compressor, alternator or power steering pump problem.
Then listen to see if the noise is from the passenger side of the engine inside the timing cover. To many possibilities hard to guess without hearing the noise first hand.