All codes › P0125
P0125: Insufficient Coolant Temperature for Closed Loop Fuel Control
What it means
The engine takes too long to reach the temperature needed for closed-loop fuel control.
Severity: Low Drivable; slower warm-up hurts economy and heater output.
Common causes
- Thermostat stuck open
- Faulty coolant temp sensor
- Low coolant
- Very cold ambient + short trips
Most common causes first. Exact causes vary by make, model and engine.
Can I fix it myself?
Often DIY. Replace the thermostat and bleed the cooling system.
Repair cost
SEEDED ESTIMATE Roughly $130–$350
Most likely repair: thermostat. Diagnosis fees, taxes and other causes are not included.
| Line | Low | High | Basis |
|---|---|---|---|
| Thermostat | $31 | $31 | Typical listed retail range, source (single example listing ($31.49); coolant not included) |
| Labor 1–2 hr | $100 | $320 | $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 P0125 are verified.
Verified reader invoices for P0125: 0. Share your repair bill to help build real costs.
Tools that can read P0125
- 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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