scan code is P0171 - system too lean. What does that mean? do I need to replace the O2 sensor, or is it something else?
Jan 14, 2010 at 9:38 AM
2005 Toyota Corolla check engine light is on
2005 TOYOTA COROLLA
MRRONALD
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The upstream O2 sensor is reading a lean fuel mixture, this could be an O2 sensor, clogged injector, low fuel pressure.
I would replace the O2 sensor, erase code. If code reappears, then measure fuel pressure with mechanical gauge to start.
I would also add a can of SeaFoam after changing O2 sensor to gas tank.
I would replace the O2 sensor, erase code. If code reappears, then measure fuel pressure with mechanical gauge to start.
I would also add a can of SeaFoam after changing O2 sensor to gas tank.
Jan 15, 2010 at 10:06 AM
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