OBD Guide

P21BF

Cold Start Cylinder 10 Injection Timing

P21BF is an OBD-II diagnostic trouble code meaning: Cold Start Cylinder 10 Injection Timing. Common causes: cylinder 10 injector malfunction, problems with injector wiring or connectors. Estimated repair cost: $22–78.

Severity
⚠️ Medium
Can you drive?
Limited driving only, diagnose soon
Approx. repair cost
$22–78 (est.)

Symptoms

  • Unstable engine operation when cold
  • Increased fuel consumption
  • Power Loss
  • Difficulty starting in cold weather
  • Increased emissions of harmful substances

Causes

  • Cylinder 10 injector malfunction
  • Problems with injector wiring or connectors
  • Engine control unit malfunction
  • Mechanical problems in the fuel supply system
  • Fuel system contamination

How to Fix

  1. Check the resistance and operation of the injector of cylinder 10
  2. Inspect the injector wiring and connectors
  3. Check control signals from the computer
  4. Clean the fuel system if necessary
  5. Replace faulty injector or other components

Related codes

Error P21BF by Vehicle Brand

FAQ

What does the P21BF code mean?

P21BF is an OBD-II diagnostic trouble code that indicates: Cold Start Cylinder 10 Injection Timing

What causes a P21BF error code?

The most common causes of P21BF include: Cylinder 10 injector malfunction; Problems with injector wiring or connectors; Engine control unit malfunction; Mechanical problems in the fuel supply system.

How do I fix a P21BF diagnostic trouble code?

To fix P21BF: Check the resistance and operation of the injector of cylinder 10. Inspect the injector wiring and connectors. Check control signals from the computer. For a complete diagnosis, use an OBD-II scanner.

Is it safe to drive with P21BF?

Limited driving only, diagnose soon

How much does it cost to fix P21BF?

The estimated repair cost for P21BF is $22–78. Actual cost depends on your vehicle, location, and labor rates.

See also: Russian version · NationStat