mysterious codes

[topher5150]

i was at the car wash put the car in neutral idled 1200 rpm and would build up rpms in Park, and doesn't rev down properly during deceleration, went to the closest Auto Zone pulled these codes: P0305 cylinder 5 misfire, P0219 fuel air metering, P0456 auxiliary emissions, and the code for the EGR valve. so I took it to Advanced Auto by my house had them check it, they only got the EGR valve code, and cylinder 5 misfire. Is it the car or the parts store

 

[Roadboss]

Probably got the wiring to the air injection pump wet. Check #5 plug and see if it is wet or what. Egr could be firing due to above.

 

[topher5150]

EGR is blocked off, cobra intake