So I just replaced the water pump & thermostat housing and are getting 3 error codes and random acceleration issues. P1497, P115D, & P15E8
I've cleaned the mass air sensor, but not dice. Any advice would be appreciated.

No mods have been made to my car.

 

What your is the car, which engine?

P1497 is a Downstream of Throttle Air Leak. If you had the intake manifold off, I would suspect something didn't sealed up correctly when reinstalling components.
It is possible that P115D is also related to a manifold leak, since the MAF signal will now be off because of the leak.
The P15E8 code has to do with the coolant temp sensor. Since you replaced the thermostat, are you sure you plugged the sensor back in completely?

Go methodically back through your work, and make sure you didn't miss anything obvious. Then double check all your connections, and try again.