P0175 indicates that the engine control module (PCM) has detected an excessively rich air-fuel mixture on Bank 2 (the side of the engine opposite cylinder #1). This means there is too much fuel or not enough air in the exhaust, causing the oxygen sensor to report a rich condition.
A faulty fuel pressure regulator can allow excess fuel to enter the intake manifold, causing a rich mixture on Bank 2. This is a common failure on many vehicles.
A stuck-open or leaking fuel injector on Bank 2 will dump extra fuel into that cylinder bank, leading to a rich condition.
A MAF sensor that over-reports incoming air volume causes the PCM to add too much fuel, resulting in a rich mixture across both banks, but the code may set on Bank 2 first.
A failed or contaminated oxygen sensor can get stuck reading 'rich' and falsely trigger the code, even if the actual mixture is correct.
If the evaporative emission control purge valve remains open, fuel vapors are continuously drawn into the intake, enriching the mixture on Bank 2.
A coolant temperature sensor that reads too cold can cause the PCM to enrich the mixture, potentially triggering a Bank 2 rich code.
You can drive short distances, but it is not recommended. A rich mixture can damage the catalytic converter and oxygen sensors over time, and fuel economy will be poor.
No. While a faulty oxygen sensor can cause this code, it is more often due to a fuel system issue like a leaking injector or fuel pressure regulator. The oxygen sensor is just reporting what it sees.
Almost never. PCM failure is extremely rare for P0175. Only consider it after thoroughly diagnosing and ruling out all other common causes, and even then it is unlikely.
Bank 2 refers to the side of the engine that does not contain cylinder #1. On V6/V8 engines, this is typically the passenger side. The code indicates the rich condition is detected on that specific bank.