on a 2002 ford F150 4.2 6 cyl . i have a service engine soon light that keeps coming on. pulled the codes they were 0171 and0174. took it to firestone , they replaced the intake manifold gasket, ran fuel system cleaner and replace the pvc tube . truck has always ran like a top. ran fine no codes for 2 days, light came back on. firestone then replaced both downstream o2s, again ran fine 2 days light back on. now theres a slight ticking sound and 2 new codes 1131and 1151. (the first two have always poped when we pulled them). what could be causing this aggrivating problem? it's driving me crazy! truck still running like a top!
Dec 15, 2010 at 4:54 PM