AutoCodes – GMC – P01D9 GMC

P01D9 GMC Code - Cylinder 8 Injection Timing Retarded

Quick Answer

The Engine Control Module (ECM) has the ability to learn injector timing performance. Common causes include Fuel Type Incorrect, Fuel Contaminated/Poor Quality, Faulty Fuel Injector 1. Severity is High - diagnose this code as soon as possible. Driving is not recommended if the warning light is flashing, the engine runs poorly, or safety-related symptoms are present.

What it means: P01D9 GMC indicates Cylinder 8 Injection Timing Retarded.
Common causes: Common causes include Fuel Type Incorrect, Fuel Contaminated/Poor Quality, Faulty Fuel Injector 1.
Severity: High - diagnose this code as soon as possible.
Can I drive?: Driving is not recommended if the warning light is flashing, the engine runs poorly, or safety-related symptoms are present.

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Code Popularity 558

How popular is this code, among other codes? Low

Repair Importance Level

Urgent (Diagnose now) (3 / 3)

Repair Difficulty Level

Advanced (Pro) (3 / 3)

What is this?

Table of contents Created and updated by William Orellana on Mar 22, 2024

Description
Possible Causes
How To Fix
Cost to Diagnose
FAQs
Comments
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Code P01D9 GMC Description

The Engine Control Module (ECM) has the ability to learn injector timing performance. When the engine is at operating temperature, throttle closed and in deceleration fuel cut-off mode, the ECM will pulse each injector individually and measure the changes in rotational speed of the crankshaft using the input from the crankshaft position sensor. The ECM will run this diagnostic at one fuel rail pressure operating point for each injector. The ECM stores the injector timing value. The Diagnostic Trouble Code (DTC) will be set when the Fuel Injection Timing is out of range.

OBDII Code P01D9 GMC - Cylinder 8 Injection Timing Retarded - AutoCodes.com — P01D9 GMC Code - Cylinder 8 Injection Timing Retarded

What does this mean?

What are the Possible Causes of the DTC P01D9 GMC?

Fuel Type Incorrect
Fuel Contaminated/Poor Quality
Faulty Fuel Injector 1
Fuel Injector 1 harness is open or shorted
Fuel Injector 1 circuit poor electrical connection
Engine Mechanical Problem

How to Fix the DTC P01D9 GMC?

Review the 'Possible Causes' above and visually examine the corresponding wiring harness and connectors. Check for damaged components and inspect connector pins for signs of being broken, bent, pushed out, or corroded.

What is the Cost to Diagnose the Code?

Labor: 1.0

To diagnose the P01D9 GMC code, it typically requires 1.0 hour of labor. Rates vary by location, vehicle, and shop. Many shops charge between $80–$150 per hour; dealerships and metro areas may be higher, independents may be lower.

Need more information about the P01D9 GMC code?

Need more information on how to fix the P01D9 GMC code? Get Access to Factory Service Manuals

Need Help with the Code?

Get the P01D9 GMC code diagnosed by a professional: Find a repair shop in your area

Information for Specific GMC Models

P01D9 2014 GMC Sierra — Cylinder 8 Injection Timing Retarded
P01D9 2015 GMC Sierra — Cylinder 8 Injection Timing Retarded
P01D9 2016 GMC Sierra — Cylinder 8 Injection Timing Retarded
P01D9 2017 GMC Sierra — Cylinder 8 Injection Timing Retarded
P01D9 2018 GMC Sierra — Cylinder 8 Injection Timing Retarded

About the author: William Orellana is a Master Mechanic and Mechanical Engineer with over 30 years of experience diagnosing and repairing vehicles. Learn more about his background.

Frequently Asked Questions about P01D9 GMC Code

1. What does the OBDII code P01D9 mean on a GMC vehicle?

P01D9 indicates that the engine control module (ECM) has detected that the injection timing for cylinder 8 is delayed or retarded beyond the acceptable range.

2. What are the common symptoms of code P01D9 in a GMC?

Symptoms may include poor engine performance, rough idling, increased fuel consumption, engine misfires, and the illumination of the check engine light.

3. What causes the P01D9 code to appear on a GMC vehicle?

Common causes include a malfunctioning fuel injector, a faulty injection timing control solenoid, wiring or connector issues, or a problem with the ECM.

4. Can I drive my GMC with the P01D9 code active?

Driving with this code is not recommended, as it can cause poor engine performance, potential damage to the engine, and increased emissions.

5. How is the P01D9 code diagnosed?

A technician will use a diagnostic scanner to confirm the code, inspect the wiring and connectors for damage, and test the fuel injector and injection timing components for proper operation.

6. What repairs can fix the P01D9 code on a GMC?

Repairs may include replacing the faulty fuel injector, repairing damaged wiring, cleaning or replacing the injection timing control solenoid, or reprogramming or replacing the ECM if necessary.

7. How much does it cost to fix the P01D9 code on a GMC?

Repair costs can vary depending on the exact cause but may range from $150 to $1,000, with fuel injector replacement being on the higher end.

8. Can a dirty fuel injector cause the P01D9 code?

Yes, a clogged or dirty fuel injector can disrupt the fuel delivery and timing, triggering the P01D9 code.

9. Will resetting the check engine light clear the P01D9 code permanently?

Simply resetting the light will not fix the underlying issue. The code will likely return if the root cause is not addressed.

10. How can I prevent the P01D9 code from recurring on my GMC?

Regular maintenance, such as fuel system cleaning, timely injector inspections, and ensuring proper electrical connections, can help prevent this code from reappearing.