P0171

Error Code P0171: System Too Lean (Bank 1)

Severity: Medium

What does P0171 mean?

System Too Lean (Bank 1)

Symptoms

  • Rough idle
  • Hesitation on acceleration
  • Poor fuel economy

Common Causes

  • Vacuum leak
  • Faulty MAF sensor
  • Weak fuel pump
  • Clogged fuel filter

How to Fix

  1. Check for vacuum leaks
  2. Clean or replace MAF sensor
  3. Test fuel pressure
  4. Replace fuel filter

Frequently Asked Questions

What does error code P0171 mean?

System Too Lean (Bank 1). This is a medium severity issue that should be addressed soon.

Can I clear P0171 with Cars Guru?

Yes. Connect your ELM327 OBD2 adapter, scan your vehicle with Cars Guru, and you can read and clear the P0171 fault code. Our AI will also explain the issue in plain language and suggest next steps.

Is it safe to drive with P0171?

It depends on the severity. Cars Guru rates this code as medium. We recommend addressing the root cause before continuing to drive. Use Cars Guru's AI diagnostics for a detailed assessment.

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