P0175 on Volvo: How to Diagnose & Fix
System Too Rich (Bank 2)
1 Volvo model · 1 documented issue · $100-$300 repair
P0175 on Volvo by model: symptoms, diagnosis and fix
The fuel pressure regulator (FPR) on the 850 is mounted on the fuel rail and uses a rubber diaphragm to regulate fuel pressure. The diaphragm deteriorates with age and heat exposure, allowing raw fuel to leak into the vacuum line connected to the intake manifold. This causes rich running, hard starting (especially hot), poor fuel economy, and a strong fuel smell. It can also foul spark plugs.
Common Symptoms
- Strong fuel smell from engine bay
- Hard hot starting
- Rich running and black exhaust smoke
- Poor fuel economy
- Fouled spark plugs
How to Fix
Replace the fuel pressure regulator. Check the vacuum line for fuel contamination and replace if saturated. Inspect and replace fouled spark plugs. The FPR is inexpensive ($30-$60) and accessible on top of the fuel rail, making this a straightforward DIY repair. Clear any stored fault codes after replacement.
P0175 code reference
General diagnostic-code context. The code alone does not confirm a cause for your vehicle; use the applicable issue card and its sources.
Frequently asked questions
What does P0175 mean on a Volvo?
P0175 stands for "System Too Rich (Bank 2)." P0175 is a generic OBD-II code meaning the engine computer detected that the air-fuel mixture on bank 2 is too rich, with too much fuel relative to air. The computer has had to remove fuel (negative fuel trim) to try to correct it but has reached its adjustment limit. Bank 2 is the cylinder bank that does not contain cylinder #1. A persistently rich mixture wastes fuel, causes rough running, and can overheat and damage the catalytic converter over time. On Volvo it is documented across 1 model: 850.
What are the most common causes of P0175?
The most common causes of P0175 are: Dirty or faulty mass air flow (MAF) sensor, Leaking or stuck-open fuel injector, Excessive fuel pressure / faulty fuel pressure regulator, Faulty or contaminated oxygen sensor, Engine vacuum leak or false air reading, Dirty/clogged air filter or restricted intake, Leaking fuel injector O-rings or fuel saturation, Faulty coolant temperature sensor skewing fuel trims. The specific cause varies by vehicle.
How much does it cost to fix P0175 on a Volvo?
Published repair estimates on Volvo range from $100 to $300 depending on the model and root cause. If an issue mentions a recall or campaign, check your VIN with the manufacturer or NHTSA and confirm eligibility and coverage with a dealer.
Looking for P0175 on a different make?
View P0175 across all makes →Content compiled with AI assistance using NHTSA complaints, TSBs, and owner reports. May contain errors. Always verify with your vehicle's service manual.