AutoCodes – Pontiac – P0442 Pontiac

P0442 Pontiac Code - Evaporative Emission Control System Leak Detected Small Leak

Quick Answer

The engine off natural vacuum test is the small leak detection diagnostic for the evaporative emission system. Common causes include Missing or loose fuel cap, Incorrect fuel filler cap used, Fuel filler cap remains open or fails to close. Severity is Low - monitor the vehicle and repair when practical. The vehicle can usually be driven if no severe symptoms are present, but symptoms should be checked before extended driving.

What it means: P0442 Pontiac indicates Evaporative Emission Control System Leak Detected Small Leak.
Common causes: Common causes include Missing or loose fuel cap, Incorrect fuel filler cap used, Fuel filler cap remains open or fails to close.
Severity: Low - monitor the vehicle and repair when practical.
Can I drive?: The vehicle can usually be driven if no severe symptoms are present, but symptoms should be checked before extended driving.

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Code Popularity 51,674

How popular is this code, among other codes? Medium

Repair Importance Level

Low (Monitor) (1 / 3)

Repair Difficulty Level

Advanced (Pro) (3 / 3)

What is this?

Table of contents Created and updated by William Orellana on Sep 30, 2023

Description
Step-by-Step Diagnostic Guide
Possible Causes
How To Fix
Tech Notes
Cost to Diagnose
FAQs
Comments
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Code P0442 Pontiac Description

The engine off natural vacuum test is the small leak detection diagnostic for the evaporative emission system. This diagnostic tests the Evaporative Emission (EVAP) system for a small leak when the key is turned OFF and the correct conditions are met. The heat from the exhaust system is transferred into the fuel tank while the vehicle is operating. Prior to running this test fuel volatility is analyzed and then factored into this test. When the vehicle is turned OFF and the EVAP system has sealed a change in the fuel tank vapor temperature occurs which results in a corresponding pressure change in the fuel tank vapor space. This change is monitored by the Engine Control Module (ECM) using the Fuel Tank Pressure (FTP) sensor input. With a leak in the system, the amount of pressure change will be less than that of a sealed system. The Diagnostic Trouble Code (DTC) will be set when the ECM detects a leak in the EVAP system that is greater than a calibrated amount.

OBDII Code P0442 Pontiac - Evaporative Emission Control System Leak Detected Small Leak - AutoCodes.com — P0442 Pontiac Code - Evaporative Emission Control System Leak Detected Small Leak

What does this mean?

What are the Possible Causes of the DTC P0442 Pontiac?

Missing or loose fuel cap
Incorrect fuel filler cap used
Fuel filler cap remains open or fails to close
Foreign matter caught in fuel filler cap
Leaking EVAP Canister
Leaking EVAP System Hose
Leaking Fuel Tank
Faulty Fuel Tank Pressure Sensor

How to Fix the DTC P0442 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 P0442 code means that the control module has detected a small leak in the Evaporative Emission (EVAP). A loose fuel tank filler cap is the most common cause that will trigger the P0442 code.

There is a factory service bulletin for all the models from 2000 through 2021. The factory states that there are seven critical connections that could likely lead to this DTC being set:
1. Purge tube to purge valve (at intake manifold)
2. Purge tube to chassis EVAP line (at the rear of the engine, near transmission)
3. Chassis EVAP line to canister (at canister)
4. Fuel tank load line to canister (at canister)
5. Vent valve line to vent valve (at vent valve)
6. Fuel tank load line jumper connection (near fuel tank)
7. Fuel tank cap is closed properly (at refuel compartment)

What is the Cost to Diagnose the Code?

Labor: 1.0

To diagnose the P0442 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 P0442 Pontiac Code

1. What are the common symptoms of OBDII code P0442 in a Pontiac vehicle?

- Common symptoms include the illumination of the check engine light, a noticeable fuel odor, and potential problems passing emissions tests.

2. What are the potential causes of OBDII code P0442 in a Pontiac?

- The code P0442 typically indicates a small leak in the evaporative emission control system, which could be caused by a loose or damaged gas cap, a cracked vacuum hose, or a faulty purge valve.

3. How serious is OBDII code P0442 in a Pontiac?

- While code P0442 is not usually a critical issue that affects vehicle performance, it should still be addressed promptly to prevent potential environmental damage and to ensure proper functioning of the emission control system.

4. How can I diagnose the cause of OBDII code P0442 in my Pontiac?

- Diagnosing the cause of code P0442 typically involves checking the gas cap for tightness, inspecting the EVAP system components for visible damage, and performing a smoke test to pinpoint the exact location of the leak.

5. What are some repair tips for fixing OBDII code P0442 in a Pontiac?

- Repair tips include ensuring the gas cap is tightened properly, replacing any damaged vacuum hoses, checking and potentially replacing the purge valve, and clearing the code with an OBDII scanner after the repairs are completed.

6. Can I drive my Pontiac with OBDII code P0442?

- It is generally safe to drive your Pontiac with code P0442, but it is recommended to address the issue as soon as possible to prevent any potential damage to the emission control system and ensure compliance with emissions regulations.

7. How much does it typically cost to repair OBDII code P0442 in a Pontiac?

- The cost of repairing code P0442 in a Pontiac can vary depending on the exact cause of the issue and the labor rates in your area. It could range from a simple fix like tightening the gas cap to more involved repairs like replacing EVAP system components.

8. Can a DIY enthusiast fix OBDII code P0442 in a Pontiac?

- Yes, some aspects of diagnosing and repairing code P0442 can be tackled by a DIY enthusiast, such as checking and tightening the gas cap or inspecting visible hoses for damage. However, more advanced diagnostics and repairs may require professional assistance.

9. Will OBDII code P0442 reset itself in a Pontiac?

- Code P0442 may reset itself if the underlying issue is intermittent and gets resolved on its own. However, it is recommended to diagnose and fix the problem to prevent the code from reoccurring.

10. How long does it typically take to repair OBDII code P0442 in a Pontiac?

- The time it takes to repair code P0442 in a Pontiac can vary based on the cause of the issue and the complexity of the repairs needed. Simple fixes like tightening the gas cap can be done quickly, while more involved repairs may take longer.