The *closest* related codes would be in the range of P0171 and P0174, which relate to lean conditions in the engine. These codes generally mean that the engine's air/fuel mixture is too lean (not enough fuel).
Possible causes for a lean condition (assuming the code is actually one of the P0171/P0174 codes, or a similar variation specific to the 1999 Taurus system), include:
* Mass Airflow Sensor (MAF) sensor: This sensor measures the amount of air entering the engine. A faulty MAF sensor can provide inaccurate readings, leading to a lean condition. This is a very common culprit.
* Vacuum Leaks: Leaks in the intake system allow unmetered air to enter the engine, again throwing off the air/fuel mixture.
* Fuel injectors: Clogged or malfunctioning fuel injectors can prevent the proper amount of fuel from being delivered.
* Fuel pump: A weak fuel pump might not deliver sufficient fuel pressure.
* Fuel pressure regulator: A faulty regulator could cause incorrect fuel pressure.
* Oxygen sensor(s): While less likely to directly cause a lean code, a bad O2 sensor can prevent the computer from properly adjusting the fuel mixture, exacerbating the problem.
What to do:
1. Double-check the code: Make absolutely sure you have the correct code. An incorrect number will lead to incorrect troubleshooting.
2. Obtain a professional diagnostic: Take your 1999 Taurus to a trusted mechanic or auto parts store with a code reader. They can accurately read the code and perform a more thorough diagnostic. A simple code reading often isn't enough, a skilled mechanic can use their experience and diagnostic tools to pinpoint the problem.
3. Consider the age of the car: Given the age of your vehicle, several components might be wearing out. The mechanic may suggest replacing parts preventative maintenance rather than focusing solely on the error code.
Don't attempt repairs based on guesses. Diagnosing and fixing fuel system problems requires specialized knowledge and tools.
