Please help. I have a 2000 SR5 4Runner, 3.4L V6 that is getting the following OBD II codes: P0171, P0135 and P0141. I recently replaced both O2 sensors with NON OEM parts. The sensors DID NOT come with an attached plug. I had to splice the wires together. I an still receiving the same codes after the replacement. I read there is a difference between the two sensors. The front sensor is a "fast" fuel ratio sensor and the rear one is a "slow" sensor. IS THIS TRUE? They both look the same. I've noticed a decrease in fuel economy and a slight hesitation on exceleration. Are these symptoms related to the O2 sensors or the Mass Air Flow sensor. What can I do?
P0171 OBD II code
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greasefingers
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P0135 - HO2S Heater Circuit Bank 1 Sensor 1
P0141 - HO2S Heater Circuit Bank 1 Sensor 2
P0171 - Fuel Trim System Lean Bank 1 (which can mean that the O2 sensor is bad or the MAP is bad
P0141 - HO2S Heater Circuit Bank 1 Sensor 2
P0171 - Fuel Trim System Lean Bank 1 (which can mean that the O2 sensor is bad or the MAP is bad