2005 Chrysler Liberty 3.7L Engine P1071 and P1072 Codes After Head Gasket Replacement
After replacing both cylinder head gaskets on my 2005 Chrysler Liberty 3.7L engine, I noticed white smoke and identified a failed O-ring in the timing chain cover gasket. The repair included full valve seat resurfacing and a complete tune-up—spark plugs, air filter, and PCV system were all serviced. One week later, the check engine light activated with codes P1071 and P1072. When I cleared these codes, they returned within five minutes after restarting the engine (turning it off and then starting again). There are no visible leaks in the intake manifold or fuel system. I initially suspected that the oxygen sensor might be reading both rich and lean conditions simultaneously, but spark plug inspections appear normal. The issue persists despite no apparent intake or fuel leaks. What should I check next? Possible causes include intake manifold issues, fuel delivery problems, or a deeper engine misfire—any guidance on diagnosing this specific P1071/P1072 combination would be greatly appreciated.
The P1071 and P1072 codes suggest a sensor or system inconsistency, possibly related to the intake manifold or fuel delivery. While timing chain misalignment is possible, it's less likely given the symptoms described. A thorough inspection of the intake gaskets and vacuum lines may be needed before considering further engine components.