P0175 Code: System Too Rich (B2) — Causes & Fix
P0175 means bank 2 is running too rich — the ECM is pulling fuel out but the mixture is still over-fuelled.
- Applies to
- All OBD-II vehicles (any make or model)
- Est. repair cost
- $40 – $600
- Time to fix
- 30 minutes – 2 hours
What it means
Causes include high fuel pressure, leaking injectors, a faulty MAF/MAP, or a contaminated O2 sensor on bank 2. P0175 is a generic OBD-II powertrain code defined in the SAE J2012 standard, so it applies to virtually any 1996-or-newer petrol car or light truck regardless of make. Fix the underlying fault, then clear the code with an OBD-II scan tool — it will return if the problem isn't resolved.
Symptoms
- Check engine light on
- Black smoke or fuel smell
- Rough idle, fouled plugs, poor economy
How to fix it
- 1
Check fuel delivery
1. Test fuel pressure. 2. Check for leaking injectors on bank 2.
- 2
Verify air-flow sensors
1. Inspect/clean the MAF and check the MAP. 2. Repair the cause, then clear the code.
Frequently asked questions
Where is bank 2?
On a V6/V8, bank 2 is the cylinder bank that does not contain cylinder 1. P0175 means that side is over-fuelled.
Last updated July 19, 2026
Guidance only — always consult a qualified professional or the official service manual before carrying out repairs.