Question

What is the meaning of the engine codes P1131 and P0401 on a 11999 Ford Ranger 2.5L?

Answer 1

Hi there

This code means there is a lack of O2 sensor switch on bank 1. This could be the result of a faulty O2 sensor or an issue with an exhaust leak or intake manifold gasket leak keeping the engine lean.

P1131 FORD - Lack of Upstream Heated Oxygen Sensor Switch Sensor Indicates Lean Bank 1
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