All codes › P0134
P0134: O2 Sensor Circuit No Activity Detected (Bank 1 Sensor 1)
What it means
The upstream O2 sensor on bank 1 (before the catalytic converter), which the computer uses to adjust fuel mixture isn't producing any signal activity.
Severity: Low–Medium No mixture feedback, so economy and emissions suffer.
Common causes
- Dead O2 sensor
- Open signal wire
- Heater failure keeping it cold
- Unplugged connector
Most common causes first. Exact causes vary by make, model and engine.
Can I fix it myself?
Often DIY. Check if a heater code is also set; a cold sensor shows no activity.
Repair cost
SEEDED ESTIMATE Roughly $70–$330
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 0.3–1 hr | $30 | $160 | $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 P0134 are verified.
Verified reader invoices for P0134: 0. Share your repair bill to help build real costs.
Tools that can read P0134
- 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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