what could be the prob?
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2004 Mazda Mazda6 Question: have code p0171
Answer #1ZeeTech October 15, 2010, 06:14Master
The P0171 indicates a lean air-fuel ratio. It could sets by several different reasons i.e.: dirty, restricted injectors, bad or dirty Mass Air Flow Sensor, disconnected or leaking vacuum hoses, leaking intake manifold gasket, leaking exhaust , O2 sensor etc...
You can check for disconnected or broken vacuum hoses and maybe clean the MAF sensor. CRC sells a good MAF cleaner, you can buy it in most parts store. Don't use other chemicals, you can damage the sensor.