OBD Guide

P21BC

Cold Start Cylinder 7 Injection Timing

P21BC is an OBD-II diagnostic trouble code meaning: Cold Start Cylinder 7 Injection Timing. Common causes: malfunction of the fuel injector of cylinder 7, problems with the fuel pump or pressure regulator. Estimated repair cost: $17–89.

Severity
⚠️ Medium
Can you drive?
Yes, but get it checked soon
Approx. repair cost
$17–89 (est.)

Symptoms

  • Unstable engine operation when cold
  • Difficulty starting at low temperatures
  • Increased fuel consumption
  • Engine failures
  • Check Engine Light Illuminates

Causes

  • Malfunction of the fuel injector of cylinder 7
  • Problems with the fuel pump or pressure regulator
  • Dirty fuel injectors
  • Coolant temperature sensor malfunction
  • Problems with the wiring to the cylinder 7 injector

How to Fix

  1. Check the condition and resistance of the injector of cylinder 7
  2. Check the pressure in the fuel system
  3. Clean or replace fuel injectors
  4. Check the operation of the coolant temperature sensor
  5. Check the integrity of the wiring to the injector

Related codes

Error P21BC by Vehicle Brand

FAQ

What does the P21BC code mean?

P21BC is an OBD-II diagnostic trouble code that indicates: Cold Start Cylinder 7 Injection Timing

What causes a P21BC error code?

The most common causes of P21BC include: Malfunction of the fuel injector of cylinder 7; Problems with the fuel pump or pressure regulator; Dirty fuel injectors; Coolant temperature sensor malfunction.

How do I fix a P21BC diagnostic trouble code?

To fix P21BC: Check the condition and resistance of the injector of cylinder 7. Check the pressure in the fuel system. Clean or replace fuel injectors. For a complete diagnosis, use an OBD-II scanner.

Is it safe to drive with P21BC?

Yes, but get it checked soon

How much does it cost to fix P21BC?

The estimated repair cost for P21BC is $17–89. Actual cost depends on your vehicle, location, and labor rates.

See also: Russian version · NationStat