Your 2000 ford windstar check engine light is on and the code reads running too lean - what does that mean?

A "running too lean" code (often P0171 or P0174, but others are possible depending on the specific bank of cylinders affected) in your 2000 Ford Windstar means the air/fuel mixture entering the engine's cylinders has too much air and not enough fuel. This is a serious issue that can cause significant damage if left unaddressed.

Several things can cause a lean condition:

* Vacuum Leaks: Cracks or holes in vacuum hoses connected to the intake manifold, PCV system, or other components can allow excess air to enter the engine, upsetting the carefully measured air/fuel ratio. This is a common culprit in older vehicles.

* Mass Airflow Sensor (MAF) Problems: The MAF sensor measures the amount of air entering the engine. If it's dirty, malfunctioning, or failing, it may provide inaccurate readings, leading to a lean condition.

* Fuel Injector Issues: Clogged or faulty fuel injectors may not be delivering enough fuel to compensate for the incoming air.

* Fuel Pump Problems: A weak or failing fuel pump can't deliver sufficient fuel pressure, resulting in a lean condition.

* Fuel Pressure Regulator Issues: This component regulates fuel pressure; a malfunction can lead to insufficient fuel delivery.

* Oxygen Sensor (O2 Sensor) Problems: Although the O2 sensor doesn't directly control the fuel mixture, a faulty sensor can provide incorrect feedback to the engine control module (ECM), which in turn adjusts the fuel mixture improperly, often leading to a lean condition.

* EGR Valve Issues: A malfunctioning EGR (Exhaust Gas Recirculation) valve can affect the air/fuel mixture.

Before attempting any repairs, it's crucial to locate the *specific* code(s) your vehicle is displaying. P0171 and P0174 are common but different (Bank 1 vs Bank 2). This will help pinpoint the problem area.

Do not continue to drive the vehicle extensively with a lean condition. Running lean can lead to overheating, engine damage, and even catastrophic engine failure.

You should:

* Inspect all vacuum hoses for cracks or leaks. This is often the cheapest and easiest first step.

* Consider professional diagnosis: Take your Windstar to a qualified mechanic for proper diagnosis and repair. They have tools (like a fuel pressure gauge) to properly assess the cause. A mechanic can also perform a smoke test to quickly identify vacuum leaks.

Ignoring this problem will likely result in more expensive repairs later. Get it checked out promptly.