Rich in cold loop after 3 years

[tww$]

Open to suggestion . Truck(turbo) has been tune running fine .For over 3 years no issue what so ever . I SLUNG the a/c belt off back this winter . So i decided to put it back on. When i did truck fired up fine .til a/c kick on it drug the engine down twice and cut off off with slight puff back fire not loud at all. i realize a/c compressor was bad , so cut a/c off .fired it back up now its rich in OPEN loop only 10. afr . i mean i have not had any engine problem in over years. i am going to start with map sensor .then intake gasket if that dont fix . suggestion

[tww$]

fixed

[DGS]

And the fix was?

[tww$]

And the fix was?

intake gasket