Question

What does the trouble code P0171 indicate on my 1998 Ford F150 4.2L?

Answer 1

Lean condition, check for vacuum leaks this is the most common cause of a lean code condition check at the PCV area the hose there tends to rupture setting lean code condition and the intake and plenum gasket area.

Answer 2

P0171 Ford Code - Fuel Injection System Too Lean Bank 1
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