P0174 on a Ford F-150
P0174 means system Too Lean (Bank 2). On the F-150, a few causes come up far more than others.
What P0174 usually means on a F-150
P0174 is the bank-2 lean code, the companion to P0171. When both set together on an F-150, the cause is almost always something that affects the whole engine, like a dirty mass airflow sensor, a PCV leak, or a weak fuel supply, rather than a single cylinder. When P0174 sets alone, look for a leak or issue specific to bank 2. On EcoBoost trucks, boost-side leaks are a frequent reason both banks read lean under acceleration.
Most common causes on the F-150
- Shared vacuum/PCV or MAF issue
Because bank-2 lean usually accompanies bank-1 lean, a common MAF, PCV, or intake-gasket leak is the first thing to check on the Triton and EcoBoost alike.
- Bank-2 intake or gasket leak
A leak isolated to the bank-2 runner or gasket leans only that side, which is why P0174 can appear without P0171.
- Boost/charge-air leak (EcoBoost)
A leaking intercooler coupler or charge pipe on the boost side lets metered air escape after the sensor, pushing bank-2 trims lean during pulls.
- Insufficient fuel delivery
A failing pump or clogged injectors can leave both banks lean, especially under load, so weak fueling shows up on bank 2 as well.
What P0174 costs to fix on a F-150
As with P0171, the typical repairs are cheap: cleaning the MAF, replacing a PCV hose, or tightening a charge-pipe clamp. A smoke test is the efficient way to localize a bank-2-only leak and is worth the small diagnostic fee. Costs climb only if fuel-supply components are the root cause.
Fixing it
If P0171 and P0174 are both present, chase a shared cause like the MAF or a PCV leak. If only P0174 is set, smoke-test bank 2's intake and charge-air path specifically.
For the full step-by-step diagnosis order (any vehicle), see the main P0174 guide.
Year, engine and mileage change the answer. Start a case and Redline weighs these causes against what your car shows, then names the check that would settle it.
Other codes on the Ford F-150
Related symptoms
Ford F-150 problems & recalls by year
Based on widely reported patterns for this model; individual causes vary by year, engine and history. Generic P0174 behavior is covered on the main P0174 page. Confirm with a scan tool before buying parts.
P0174 on your F-150?
Every problem becomes a Case. Tell Redline what your F-150 is doing: it shows what the evidence supports, what’s still missing, and what to check next, before you approve a repair.
“Inner pad ~1 mm. Outer pad 3 mm.”
Next: check the slide pins move freely before buying parts.