2004 Mazda MPV Q&A
2004 Mazda MPV Question: What does CODE P0174 Bank2 System To Lean mean?
They love to sell parts; Could be but need further diagnosis to be sure. Check for vacuum leak, air intake tubing on engine side of MAF sensor. Another thing I have had intake manifold leaks from loose bolts. - ProfessorG
3.0 DOHC Ford engines, which you have, are famous for vacuum leak @ large rubber (reducing tubing connector) under the intake manifold. Hard to see this! Also the entire pcv valve circuit, including the valve! Is idle speed erratic, up and down after running a few minutes? - pushrod
NEVER I repeat NEVER let a parts guy diagnose your vehicle,all due respect to any parts people that read this but I have made ALOT of money fixing autozone lean code/o2 sensor diagnostics. Just get them to pull the code and ask us,we got you're back....but not you're o2 sensor,just kidding. - bmdouble