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PO174 Diagnostic and Fix for 2007 Ford F-150 4.6L Engine - Check Engine Light & Lean Condition

Model: 2007 F-150 Fault Code: P0174 Posted: 2014-12-09 19:27

The check engine light has come on in my 2007 Ford F-150 with a 4.6L V8 engine, accompanied by the battery light. I replaced the battery and reset the Powertrain Control Module (PCM), but during this process, the truck stalled. After diagnosing and replacing the fuel pump and fuel filter, I am now receiving a PO174 code indicating a lean condition on Bank 2. I performed a vacuum leak test with no detected leaks. All spark plugs and coil packs have been inspected and are in good condition. The Mass Air Flow (MAF) sensor was replaced, but the issue persists. The EGR valve has also been checked and cleaned; the throttle body was similarly cleaned. This truck has 111,000 miles on it. I'm seeking advice on how to resolve this PO174 lean condition specifically on Bank 2. Any insights or diagnostic steps would be greatly appreciated.

Related fault codes
P0174
Comments (2)
Anonymous 2014-12-10 11:25

If the lean condition only occurs at idle and improves when engine RPM increases, a vacuum leak on Bank 2 is likely. Check the live data for lambda (O2) sensor readings on both banks. Perform a quick throttle test from idle to 3000 RPM to observe if the pre-cat O2 sensor transitions between rich and lean states.

Anonymous 2014-12-11 19:42

Inspect all vacuum hoses, especially those that are disconnected or have cracked PVC grommets—these are common sources of vacuum leaks on Bank 2 in 4.6L F-150 engines.