2004 Ford F15-0 STX 4.6L V8 Throws Multiple Codes (PO174, PO308, PO316) - What Could Be Causing This?
I own a 2004 Ford F150 STX with a 4.6L V8 engine that began running poorly last week. After connecting a OBD-II code reader, I received the following diagnostic trouble codes: PO174, PO308, and PO316 — each appearing twice. The repeated occurrence of these codes suggests a persistent issue. Possible causes include faulty spark plugs or wires, defective coil packs, weak fuel injector performance, low engine compression, or problems with the oxygen sensor or catalytic converter. Given that my truck is used daily, I'm concerned about potential breakdowns and need reliable guidance on diagnosing and fixing this issue.
Start with code P0308. This code typically indicates a misfire in cylinder 8. Possible causes include: faulty spark plug or ignition wire, defective coil pack, malfunctioning oxygen sensor, fuel injector failure, burned exhaust valve, catalytic converter issue, low fuel level, poor engine compression, or a faulty engine control module (ECM). For more detailed information, refer to official OBD-II code P0308 documentation.