How to fix P0442 obd2 code?

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How to fix P0442 obd2 code
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If you are looking for how to fix the P0422 obd2 code, you are probably in the right place. DTC (diagnostic trouble code) P0442 is an OBD2 code that indicates EVAP small leaks. You can conveniently diagnose and fix the problem. We have created this brief handout to help you through the process. 

OBD2 Code P0442; What is it and what does it indicate?

OBD2 Code P0442; What is it and what does it indicate?

When your vehicle shows DTC P0442, it is an indication that there is any kind of small or minor leaks in the EVAP system. It can happen for variable reasons. Therefore, to resolve the issue, you need to understand the root cause of the problem. 

OBD2 P0442 Code Error; Causes 

The most common causes for the obd2 code p0442 are;

  • The fuel cap can be damaged, leak, or lose. 
  • Leaked or damaged EVAP system line.
  • Broken, leaked, or damaged charcoal canister
  • Fuel tank leak or damage.
  • Internal leaking of a vent valve 
  • Purge valve leaking 
  • Default in FTP sensor
  • Leaking or failed detection pump

OBD2 Error Code P0442; Symptoms

To understand or notice if your car is having leaks in the EVAP system, you must look out for a few signs, like;

  • If your vehicle is illuminating Check the Engine Light 
  • If you notice your vehicle is emitting a higher amount of emission.
  • The smell of strong gasoline under unusual conditions.

OBD2 P0442 Code Error; Diagnosis

If you are going to diagnose code p0442, you will most probably need a code reader or OBD scanning tool to clear the code. Start by connecting a scanning tool to the DLC port on the car and look for any codes and freeze frame data. You can determine when the issues started with the help of data. 

  • When dealing with a P0442 code, the first thing you should do is double-check that the gasoline cap is securely fastened, since a loose cap can easily cause the code to appear. If tightening the cap doesn’t work, you could consider buying and installing a new one.
  • Smoke tests use a special machine that fills the EVAP system with smoke. It helps in visually evaluating the EVAP system for any evident cracked or broken components. Also, look for any loose or damaged EVAP lines.
  • Check for damaged plastic pieces and/or split or disconnected hoses. 
  • Inspect the fuel tank and the charcoal canister for cracks.
  • Monitor tank pressure with a scan tool to see whether a leak is present.
  • The solenoids and valves of the EVAP system should be checked with a scan tool.

Mistakes to Avoid When Diagnosing The P0442 Code

If you are following proper guidelines and steps, you can conveniently diagnose p0442 code error OBD2. Most commonly, this issue is due to loss or damaged gas cap. Firstly, looking for a malfunctioning gas cap can save you from the effort of going through examining all other components related to Code P0442 error. 

How To Fix P0442 Evaporative Emission Control System Incorrect Purge Flow

How To Fix P0442 Evaporative Emission Control System Incorrect Purge Flow

Several factors contribute to a code P0442 OBD2 error. Therefore, you cannot say if this particular reason is the one. If you want to fix this error code, you’ll need to do a few fixes or replacements. Fixing an issue needs your undivided focus on all the related problems. The following are some ways to resolve the OBD Code P0442 error:

  • Replace the faulty, lost, or damaged gas cap.
  • If there are any problems with the gasoline tank, it must be replaced.
  • Immediately fix or replace the faulty charcoal canister.
  • Ensure that the EVAP system lines are free from any damage or leaking.
  • Changing malfunctioning the purge and vent valves

Vehicles that usually face P0442 issues?

  • Chevrolet
  • Ford
  • Dodge
  • Pontiac
  • Mazda
  • Acura
  • GMC


What is the impact of a little EVAP leak?

Most commonly, people ignore the check engine light. They pay no heed to it until their service visit is due. However, it’s not a good idea to keep driving your vehicle if it shows the check engine light. The EVAP leak can be of any reason that can lead to a serious and ecologically hazardous problem in the future. 

What does it cost to repair a minor EVAP leak?

Repairing an EVAP system might cost anything from $100 to $600. The cost of repair is determined by two factors: the location of the leak and the source of the leak. Other causes, on the other hand, will only necessitate a little repair that will not be as costly.

Can you drive with an EVAP leak for a long time?

The EVAP leak does not cause any significant issues immediately. However, it is suggested that you should not drive your vehicle with an EVAP leak for more than 30 to 50 miles.

Is it possible for an EVAP leak to cause a misfire?

The EVAP system consists of various components and it is directly linked to a vehicle’s fuel-air mixture. Therefore, there are chances of a vehicle misfire depending on what and how serious the issue is. 

Will an EVAP leak fail an emission test?

An Evaporative Emission Control (EVAP) System, controls the vapors generated by the fuel system in your car. If these pollutants escape into the environment, your automobile will fail the emissions test. Your EVAP system might have leaks, earning you an F.