Code 300 is for a random miss. 172 and 175 are for the same problem - 172 is for a rich fuel mixture bank one and 175 is for the fuel mixture too rich on bank two. Code 143 is for a rich mixture for sensor number 3. All of the codes could be connected to a leaking injector or other fuel problem. Very seldom are all of the O2 sensors faulty at the same time.
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Code 300 is for a random miss.
172 and 175 are for the same problem - 172 is for a rich fuel mixture bank one and 175 is for the fuel mixture too rich on bank two.
Code 143 is for a rich mixture for sensor number 3.
All of the codes could be connected to a leaking injector or other fuel problem. Very seldom are all of the O2 sensors faulty at the same time.