why does The code# 1174 keeps coming on.

Question

code # 1174 keeps coming on after a 30 mile run. changed both 02 senors and its been at the dealership 3 times, every thing is stock on engine and the dealer can not figure out y it keeps coming on. the vehicle has 49000 miles on it

Answer 1

P1174 Fuel trim cylinder balance

The only known solution for this is to perform a fuel injection cleaning,