Hi there,
P0100 code is for a faulty mass air flow sensor. It is quite possible the sensor itself is the cause of the code. You do need to check the wiring however as the could would also appear if there isn't any power to the maf sensor.
P0325 this code is for the knock sensor. This is mounted under the lower intake manifold. It's important to know that this code won't turn the light on and should be the last repair you make. It won't affect the way the truck runs in a noticeable manner.
P0138 This code is for the bank 1 O2 sensor, sensor 2. This is the sensor AFTER the catalytic converter on the passenger side of the engine. Most often the sensor itself is the problem. I would start these repairs by replacing the maf sensor and clearing the codes, then see if the O2 sensor code comes back or not. With a bad maf sensor it's possible the code is caused by that.
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P0100 code is for a faulty mass air flow sensor. It is quite possible the sensor itself is the cause of the code. You do need to check the wiring however as the could would also appear if there isn't any power to the maf sensor.
P0325 this code is for the knock sensor. This is mounted under the lower intake manifold. It's important to know that this code won't turn the light on and should be the last repair you make. It won't affect the way the truck runs in a noticeable manner.
P0138 This code is for the bank 1 O2 sensor, sensor 2. This is the sensor AFTER the catalytic converter on the passenger side of the engine. Most often the sensor itself is the problem. I would start these repairs by replacing the maf sensor and clearing the codes, then see if the O2 sensor code comes back or not. With a bad maf sensor it's possible the code is caused by that.
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