have code p0171

"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. Zee" I second that!