OBD Guide

P029B

Cylinder 1 - Fuel Trim at Min Limit

P029B is an OBD-II diagnostic trouble code meaning: Cylinder 1 - Fuel Trim at Min Limit. Common causes: dirty or faulty fuel injector of cylinder 1, vacuum leak in the intake tract. Estimated repair cost: $56–167.

Severity
⚠️ Medium
Can you drive?
Limited driving only, diagnose soon
Approx. repair cost
$56–167 (est.)

Symptoms

  • Unstable engine idling
  • Power Loss
  • Increased fuel consumption
  • Detonation (engine knocking)

Causes

  • Dirty or faulty fuel injector of cylinder 1
  • Vacuum leak in the intake tract
  • Malfunction of the mass air flow sensor (mass air flow sensor)
  • Intake manifold leaking
  • Problems with the fuel pump or fuel pressure regulator

How to Fix

  1. Check the fuel injector of cylinder 1 for contamination and performance.
  2. Inspect the intake tract for vacuum leaks
  3. Check the MAF readings and replace if necessary
  4. Check the intake manifold for leaks
  5. Check the fuel pressure in the system

Related codes

Error P029B by Vehicle Brand

FAQ

What does the P029B code mean?

P029B is an OBD-II diagnostic trouble code that indicates: Cylinder 1 - Fuel Trim at Min Limit

What causes a P029B error code?

The most common causes of P029B include: Dirty or faulty fuel injector of cylinder 1; Vacuum leak in the intake tract; Malfunction of the mass air flow sensor (mass air flow sensor); Intake manifold leaking.

How do I fix a P029B diagnostic trouble code?

To fix P029B: Check the fuel injector of cylinder 1 for contamination and performance.. Inspect the intake tract for vacuum leaks. Check the MAF readings and replace if necessary. For a complete diagnosis, use an OBD-II scanner.

Is it safe to drive with P029B?

Limited driving only, diagnose soon

How much does it cost to fix P029B?

The estimated repair cost for P029B is $56–167. Actual cost depends on your vehicle, location, and labor rates.

See also: Russian version · NationStat