AutoCodes – Pontiac – P0172 Pontiac

P0172 Pontiac Code - Fuel Trim System Rich Bank 1

Quick Answer

The Engine Control Module (ECM) controls a Closed Loop air/fuel metering system to provide the best possible combination of drivability, fuel economy, and emission control. Common causes include Dirty or Faulty Mass Air Flow (MAF) Sensor, Intake Air Leaks, Exhaust Gas Leaks. 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: P0172 Pontiac indicates Fuel Trim System Rich Bank 1.
Common causes: Common causes include Dirty or Faulty Mass Air Flow (MAF) Sensor, Intake Air Leaks, Exhaust Gas Leaks.
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 31,439

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 May 29, 2022

Description
Step-by-Step Diagnostic Guide
Possible Causes
How To Fix
Tech Notes
Cost to Diagnose
FAQs
Comments
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Code P0172 Pontiac Description

The Engine Control Module (ECM) controls a Closed Loop air/fuel metering system to provide the best possible combination of drivability, fuel economy, and emission control. The ECM monitors the Heated Oxygen Sensor (HO2S) signal voltage and adjusts the fuel delivery based on the signal voltage while in Closed Loop. A change made to the fuel delivery changes the long and short-term fuel trim values. The short-term fuel trim values change rapidly in response to the HO2S signal voltages. These changes fine-tune the engine fueling. The long-term fuel trim values change in response to trends in the short-term fuel trim. The long-term fuel trim makes coarse adjustments to fueling to re-center and restore control to short-term fuel trim. The ideal fuel trim values are around 0 %. A positive fuel trim value indicates that the ECM is adding fuel to compensate for a lean condition. A negative fuel trim value indicates that the ECM is reducing the amount of fuel to compensate for a rich condition. The Diagnostic Trouble Code (DTC) will be set when the average long-term fuel trim weighted average value is greater or less than a calibrated value.

OBDII Code P0172 Pontiac - Fuel Trim System Rich Bank 1 - AutoCodes.com — P0172 Pontiac Code - Fuel Trim System Rich Bank 1

What does this mean?

What are the Possible Causes of the DTC P0172 Pontiac?

Dirty or Faulty Mass Air Flow (MAF) Sensor
Intake Air Leaks
Exhaust Gas Leaks
Fuel Contamination
Faulty or Leaking Fuel Injectors
Faulty Front Heated Oxygen Sensor
Ignition Misfiring
Incorrect Fuel Pressure
Positive Crankcase Ventilation (PCV) Hose Leaks

How to Fix the DTC P0172 Pontiac?

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 does this mean?

Code Tech Notes

The P0172 code means that more gasoline is detected in the exhaust gases exiting the combustion chamber. If the P0172 is set in along with the P0175 code, it is highly likely that the problem is caused by leaking fuel injectors. If there are no leaking fuel injectors, the next step is to replace the air filter and clean the Mass Air Flow (MAF) Sensor. If the problem persists the MAF or Front Heated Oxygen (O2) Sensor will need to be replaced.

Click Here to Learn What is Bank 1 and Bank 2

There is a Factory Service Bulletin for the following Pontiac models:
2000-2001 Pontiac Transport
2000-2002 Pontiac Firebird
2000-2008 Pontiac Bonneville
2000-2008 Pontiac Grand Am
2000-2008 Pontiac Grand Prix
2000-2008 Pontiac Sunfire
2001-2008 Pontiac Aztek
2002-2008 Pontiac Montana
2000-2008 Pontiac Factory Service Bulletin OBDII Code P0172

What is the Cost to Diagnose the Code?

Labor: 1.0

To diagnose the P0172 Pontiac 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.

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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 P0172 Pontiac Code

1. What does OBDII code P0172 for Pontiac mean?

- OBDII code P0172 indicates that the fuel trim system on Bank 1 is detecting a rich condition, meaning there is too much fuel being injected relative to the amount of air present.

2. What are common symptoms of a P0172 code on a Pontiac?

- Common symptoms of a P0172 code include poor fuel economy, rough idling, engine misfires, black smoke from the exhaust, and a strong smell of fuel.

3. What are possible causes of a P0172 code on a Pontiac?

- Possible causes of a P0172 code include a faulty oxygen sensor, vacuum leaks, a clogged fuel injector, a malfunctioning mass airflow sensor, a dirty or clogged air filter, or issues with the fuel pressure regulator.

4. How can I diagnose a P0172 code on my Pontiac?

- Diagnosing a P0172 code typically involves checking for vacuum leaks, inspecting the oxygen sensor, testing the fuel injectors, examining the mass airflow sensor, and ensuring the air filter is clean.

5. Can a P0172 code be triggered by a bad fuel pump on a Pontiac?

- While a bad fuel pump is not a common cause of a P0172 code, it can indirectly contribute to a rich condition by delivering too much fuel to the engine. However, other components are usually more likely culprits.

6. How serious is a P0172 code on a Pontiac?

- A P0172 code should be addressed promptly to prevent potential damage to the engine and to ensure optimal fuel efficiency. Ignoring the code could lead to further issues over time.

7. Can I drive my Pontiac with a P0172 code?

- It is not recommended to drive your Pontiac with a P0172 code, as it can lead to decreased fuel efficiency, engine performance issues, and potential damage if left unresolved.

8. How much does it cost to repair a P0172 code on a Pontiac?

- The cost to repair a P0172 code on a Pontiac can vary depending on the underlying cause. Simple fixes like replacing an oxygen sensor may cost a couple of hundred dollars, while more complex issues could run into the thousands.

9. How long does it take to fix a P0172 code on a Pontiac?

- The repair time for a P0172 code on a Pontiac depends on the specific cause and the extent of the issue. Simple fixes can be completed in a few hours, while more involved repairs may take longer.

10. Can I reset a P0172 code on my Pontiac by disconnecting the battery?

- While disconnecting the battery can clear the code temporarily, it is not a recommended method for resolving the underlying issue causing the P0172 code. It is best to diagnose and address the root cause of the problem.