P0170 - Fuel Trim Malfunction (Bank 1)

Fuel trim correction on bank 1 has reached an abnormal limit.

Code Overview

Fuel trim correction on bank 1 has reached an abnormal limit.

Common Causes

• Vacuum leak
• Dirty or faulty MAF sensor
• Fuel pressure issue
• Injector problem
• Exhaust leak before O2 sensor

Diagnostic Steps

1. Check short- and long-term fuel trims
2. Inspect for vacuum leaks
3. Check MAF and air filter
4. Verify fuel pressure if possible

Likely Repairs & Cost Guides

Use test results to confirm the fault before pricing the repair.

Related OBD Codes

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Next Steps

Move from the code to a diagnosis path, then into repair pricing once the fault is confirmed.