What causes fuel trim system lean?
The lean condition can be caused by a vacuum leak, which introduces more air into the air-fuel mixture, or by a weak fuel system, which does not input enough fuel into the air-fuel mixture.
What does it mean when system is too lean?
The OBDII trouble code P0171 – System Too Lean (Bank 1) means that the engine air-fuel mixture is too lean, or there is too much air and too little fuel. Driving a car with the code P0171 can cause more damage to the engine over time, as when the engine runs lean, the combustion temperature is higher.
What happens when Toyota fuel system is too lean?
This will skew the signal of the Toyota’s on board computer and will result in a severe lean condition and will bog or hesitate under a load or while trying to accelerate. Sometimes you can clean the sensor element but most of the time replacement is necessary.
Why does my Toyota Corolla have a lean engine?
The problem may be on a much smaller scale where the computer on the Toyota Corolla can compensate for the lean condition and the driver may never feel a hiccup while driving. I will go over some of the more common ones I have seen on a Toyota Corolla and even the Toyota Matix as they use the same 4 cylinder engine.
Where is the mass air flow sensor on a Toyota Camry?
According to that TSB, they also make a special socket (part number 09224-00010) to remove and replace the air fuel ratio sensor. Here is a picture of a mass air flow sensor on a 2008 Toyota Rav4. This is the same engine, sensor and set up as the 07 Toyota Camry with a 2.4 liter engine.
Is the MAP sensor on a Toyota Corolla too lean?
For example, a 1998 Toyota Corolla uses a MAP sensor intead of a MAF sensor. The O.E. part number for the MAP sensor on this vehicle is 8942002030. While the MAP sensor may go bad, it is not very common. Even if it did go bad, I have not seen it flag a lean code.
https://www.youtube.com/watch?v=X5GaA9cP_94