OBD Guide

P01D9

Cylinder 8 Injection Timing Performance - Over Retarded

P01D9 is an OBD-II diagnostic trouble code meaning: Cylinder 8 Injection Timing Performance - Over Retarded. Common causes: malfunction of the fuel injector of cylinder 8, problems with the fuel pump or pressure regulator. Estimated repair cost: $56–167.

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

Symptoms

  • Misfire in cylinder 8
  • Reduced engine power
  • Increased fuel consumption
  • Unstable idle

Causes

  • Malfunction of the fuel injector of cylinder 8
  • Problems with the fuel pump or pressure regulator
  • Contaminated or damaged fuel lines
  • Malfunction of sensors (mass air flow sensor, camshaft position sensor, crankshaft position sensor)
  • Problems with the wiring harness or injector contacts

How to Fix

  1. Check the condition of the fuel injector of cylinder 8
  2. Check the fuel pressure in the system
  3. Check the condition of the sensors and their wiring
  4. Clean or replace fuel lines if necessary
  5. Check and update ECU software

Related codes

Error P01D9 by Vehicle Brand

FAQ

What does the P01D9 code mean?

P01D9 is an OBD-II diagnostic trouble code that indicates: Cylinder 8 Injection Timing Performance - Over Retarded

What causes a P01D9 error code?

The most common causes of P01D9 include: Malfunction of the fuel injector of cylinder 8; Problems with the fuel pump or pressure regulator; Contaminated or damaged fuel lines; Malfunction of sensors (mass air flow sensor, camshaft position sensor, crankshaft position sensor).

How do I fix a P01D9 diagnostic trouble code?

To fix P01D9: Check the condition of the fuel injector of cylinder 8. Check the fuel pressure in the system. Check the condition of the sensors and their wiring. For a complete diagnosis, use an OBD-II scanner.

Is it safe to drive with P01D9?

Limited driving only, diagnose soon

How much does it cost to fix P01D9?

The estimated repair cost for P01D9 is $56–167. Actual cost depends on your vehicle, location, and labor rates.

See also: Russian version · NationStat