P0175

System Too Rich Bank 2

Fuel & air metering Generic OBD-II High

What it means

P0175 means the engine on bank 2 (the cylinder bank without cylinder 1) is running with too much fuel relative to air, and the ECM has hit the limit of how far it can trim fuel back. It usually points to a false-high airflow reading, leaking injectors, or high fuel pressure. The car still drives, but the rich mixture hurts economy and can damage the catalytic converter over time.

High

Can I keep driving? Drivable, but a persistently rich mixture wastes fuel, can foul plugs, and over time can damage the catalytic converter — don't leave it unaddressed.

Real-world scan data

Seen in

401

scans in the past year

Found in

0.1%

of scans

0.1%

of scans that found faults

Appears alongside · share of P0175 scans

P0172in 78.5% of scans

P1000in 22.2% of scans

Figures reflect only diagnostic scans recorded through our own apps and tools. Cars are typically scanned because a symptom or warning light prompted it, so these counts describe our scan records — not the incidence of faults in any model, and not the quality, reliability, or safety of any vehicle. No comparison between manufacturers or models is implied. All trademarks belong to their respective owners; no affiliation or endorsement is implied.

Common symptoms

What you'll notice

Check-engine light on
Poor fuel economy
Strong fuel smell from the exhaust
Rough running, and black smoke under load

Common causes

Most likely first

Contaminated or skewed mass airflow (MAF) sensor over-reading airflowLikely
Leaking or dripping fuel injectors on bank 2Common
Excessive fuel pressure (failed regulator)Common
Faulty upstream oxygen sensor on bank 2Less often
Failed engine control module (rare)Less often

How to diagnose & fix

Work through it in order

Read fuel-trim data — heavily negative long-term trim on bank 2 confirms the rich condition.
Inspect and clean the MAF sensor and check for false airflow readings.
Check fuel pressure against spec and inspect injectors for leaks.
Test the bank 2 upstream O2 sensor's response and wiring.
Repair the confirmed cause, then clear the code and recheck fuel trims.

FAQ

Quick answers

Is it safe to drive with P0175?+

Short term, yes, but running rich wastes fuel and can overheat and damage the catalytic converter, so repair it before long trips.

Can I just clear P0175?+

It'll come back — the ECM will re-detect the rich mixture on the next drive cycles until the underlying fault is fixed.

Read & clear P0175 yourself

Scan your car, confirm the code, and clear it once it's fixed — with OBD DashX on your phone.

▶ Get it on Google Play

✓ Verified name — SAE J2012 / ISO 15031-6Guidance reviewed by OBD DashX