Q: Problem was misfire cylinder 5 - replaced plugs, wires, ignition coil, MAF, PCV, now I have code P0174 indicating vacuum leak.

asked by on July 05, 2017

Original problem was "misfire cylinder 5." Replaced plugs, wires and ignition coil. Next P0148 - replaced MAF. Then got codes P0174 and P0171. Replaced PCV. Now the P0174 remains - Fuel System Too Lean (Cylinder Bank 2). What is the next step?

My car has 108500 miles.
My car has an automatic transmission.

P0174 can set if: there is an air leak after the mass air flow (MAF) sensor, such as a torn intake boot, or bad intake manifold gaskets; a dirty or faulty mass air flow sensor; a faulty oxygen sensor, incorrect fuel pressure, a leaking positive crankcase ventilation (PCV) valve, a clogged exhaust gas recirculation (EGR) port, and/or a leaking brake booster. To have these possibilities ruled in or out, the recommended service is a check engine light diagnostic - Code P0174. If you request that service, the responding certified mechanic will get this taken care of for you. If you have further questions or concerns, do not hesitate to re-contact YourMechanic as we are always here to help you.

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