All codes › P0151
P0151: O2 Sensor Circuit Low Voltage (Bank 2 Sensor 1)
What it means
Voltage from the upstream O2 sensor on bank 2 (before the catalytic converter), which the computer uses to adjust fuel mixture is stuck low (V-engines).
Severity: Low–Medium Bank 2 mixture feedback lost; economy may drop.
Common causes
- Failed bank 2 upstream sensor
- Exhaust leak
- Shorted wiring
- Lean condition on bank 2
Most common causes first. Exact causes vary by make, model and engine.
Can I fix it myself?
Sometimes DIY. Bank 2 sensors on transverse V6s can be behind the engine. Tight access.
Repair cost
SEEDED ESTIMATE Roughly $90–$410
Most likely repair: oxygen sensor. Diagnosis fees, taxes and other causes are not included.
| Line | Low | High | Basis |
|---|---|---|---|
| Oxygen sensor | $36 | $168 | Typical listed retail range, source |
| Labor 0.5–1.5 hr | $50 | $240 | $100–$160/hr, shop survey |
⚠️ This is an editorial placeholder range for this type of repair. It is not based on real invoices or licensed pricing data yet. Real ranges will appear here once enough reader invoices for P0151 are verified.
Verified reader invoices for P0151: 0. Share your repair bill to help build real costs.
Tools that can read P0151
- ScanFixAI: Pro $29.99/mo or $249.99/yr
- OBDAI: Annual PRO bundle $299
- BlueDriver Pro Next-Gen: $119.95 list ($99.95 sale seen)
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