Oil pump? Afm Cylinder 4 misfire

[My07sh*tbox]

Newb here. My 07 Yukon has been in the shop over a week now. (Local mechanic)  Have had the vehicle about a year, changed the oil regularly, replaced oil sensor and sending unit due to the infamous low oil pressure warnings. Thing has driven great until randomly one day she started idle hard and misfired when going into first. I changed all sparks, plugs. No change. Shop is saying my oil pump is completely shot..?  I've had no noise no other signs of it starting to fail. My sensor would routinely go off a month prior to oil change being due. Do these things really just crap out?  Could it be related to my misfire? They are checkin the head on that, otherwise she drove normal and smooth once I go over 15mph. If she survives and my wallet doesn't get drained, I will be disabling the AFM. 

[MaverickZ71]

You posted in the HD section.  You'll get a better response if you post in the 1500 (light duty) section under the powertrain (including AFM) questions.  

[Paintor]

Sell it.

[Formulabruce]

Clean the throttlebody with Thottle body cleaner, and both sides of the throttle plate, make it perfect, and try it again.  This doesnt sound any oil pump issue