Error P0442 – how to fix?

Hi-ya!,good afternoon. In the following paragraphs you will see a description of fuses and relays Error P0442 – how to fix?

Include with pics of block diagrams in addition to their locations. Highlighted the cigarette lighter fuse (as the most famous thing people look for).
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P0442 Code Definition

P0442 is a diagnostic trouble code (DTC) that is displayed when the evaporative emission control system malfunctions. This code may be visible with other EVAP system codes.

What does the code P0442 mean

P0442 occurs on vehicles that have a small leak in the EVAP system. The ECU carefully monitors the EVAP system for possible leaks or irregularities, and if a small leak is detected, the ECU sets the Check Engine light, which is displayed on the instrument cluster.

What causes the P0442 code?

  • Faulty or loose fuel cap
  • Leak in the EVAP line
  • There is a leak in the charcoal canister
  • Leak in the fuel tank
  • Defective vent or bleed valve

What are the symptoms of the P0442 code?

  • The Check Engine light is present on the dashboard.
  • Some vehicles may show a slight decrease in gas mileage with an EVAP leak.

How can a mechanic diagnose the P0442 code?

  • Plug the scan tool into the vehicle’s DLC port and check for codes present.
  • Examine the frozen data frames associated with the code showing the circumstances of the vehicle when the fault occurred.
  • Clears codes and tests vehicle
  • Performs a visual inspection of the EVAP system for obvious cracked or broken components and loose or damaged EVAP cables.
  • Check for cracks in the fuel tank or charcoal canister.
  • Check the tightness and condition of the fuel cap and check it with a fuel cap tester.
  • Use a scan tool to monitor the pressure in the tank and confirm if there is a leak.
  • Checks solenoids and valves of the EVAP system with a scan tool
  • Perform a smoke test on the EVAP system looking for any smoke that indicates a vapor leak.

The most common errors when diagnosing the P0442 code

  • Skilled technicians should have little trouble diagnosing P0442 as long as all steps are followed in the correct sequence and none are skipped.
  • Often times the fuel cap is causing P0442, if the fuel cap is overlooked it can waste time and energy diagnosing other components.

How serious is the P0442 code?

P0442 usually has no negative symptoms other than the presence of the Check Engine light. When this code appears, fuel vapors are leaking from the EVAP system into the atmosphere. You may notice a slight decrease in fuel consumption with this code.

What repairs can remove the P0442 code?

  1. Replacing the fuel cap
  2. Fuel tank replacement
  3. Replacing the carbon cartridge
  4. Replace the EVAP wiring
  5. Replace bleed or vent valves

Additional notes regarding the P0442 code

Professional grade tools make diagnosing a P0442 leak much easier and more accurate. An advanced scanning tool that allows you to access live data and monitor your EVAP system is very useful when dealing with the P0442 code or any EVAP code at all.

Some vehicles have the option to be ordered with a scan tool to test the EVAP system for proper operation of all components, and can be used to help isolate which part of the system is damaged or leaking.

As fuel vapors, most EVAP leaks are much smaller than the eye can see. The smoke test is performed to find hard-to-detect fuel vapor leaks. This is done using a specialized fuming machine that pressurizes the fuel system and adds smoke to reveal small leaks.

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