I have a toyota echo 2001 with engine code p0171 could it be the injectors?

Question

I have replaced the intake , the maf ,and the o2 sensor.

Answer 1

HI there,

It's not usually the injectors, however low fuel pressure can cause it, also the front O2 sensor can give you the lean fuel mixture. Once in a while the catalytic converter can cause it as well if the exhaust is blowing back over the front O2 sensor.