could a crack in my intake manifold cause my car to run lean?

the other day when i was doing some pullson the highway i noticed my car was running lean, not terrible but about 12.5- 13 on my wideband, so i pulled over to check everything out, nothing really noticable was wrong under the hood but when i started looking at my honda logger i noticed my map sensor was reading about a pound or more less preasure than normal with my turboed car so i checked for boost leaks and found a pretty nasty one in the intake manifold

 

A crack in the manifold where it is actually leaking out will cause a crazy surging idle that isn't anywhere near spec.

Have conditions changed dramatically since it was tuned? Temperature, altitude, new parts?

 

its only leaks when im boosting enough for air to leak, and there hasnt been any real change in tune