P0442: How to Diagnose & Fix — Evaporative Emission Control System Leak Detected (Small Leak)
32 vehicles · 15 makes · $20-$900 repair
How to diagnose and fix P0442: most-reported vehicles
Ranked by owner reports. Each card gives the symptoms, how to confirm the cause, the fix, parts and sources for that vehicle.
Ford Transit Connect · 2014–2021
Owners report extended cranking, rough idle, or stalling shortly after refueling due to an EVAP canister purge valve that sticks open and floods the intake with fuel vapor. This failure mode is documented across Ford applications and appears in Transit Connect owner reports and service literature addressing purge valve performance. The condition often triggers EVAP-related DTCs and can worsen over time.
Common Symptoms
- Hard start immediately after refueling
- Rough idle or stumble after fill-up
- Occasional stall when coming to a stop
- Fuel odor near engine bay
- Check engine light on
How to Fix
Replace the EVAP canister purge valve/solenoid and inspect EVAP lines for liquid fuel contamination. Clear codes and verify proper purge operation with scan tool commands; advise against topping off the tank to reduce recurrence risk.
Sources for this issue (1)
Chevrolet HHR · 2006–2011
The HHR has a documented issue with fuel line corrosion, particularly in rust belt states. The fuel line corrodes just forward of the driver-side rear wheel, developing leaks that create a fire hazard. Road salt and debris accelerate the corrosion. The issue is most commonly seen on vehicles in the northeastern and midwestern United States where road salt is used heavily in winter.
Common Symptoms
- Gasoline smell near the vehicle
- Visible fuel drip under vehicle near rear driver-side wheel
- Fuel economy decreasing noticeably
- Rust or corrosion visible on fuel lines during inspection
- Check engine light with evaporative system codes
How to Fix
Inspect fuel lines annually, especially near the driver-side rear wheel. If corrosion is found, replace the affected fuel line section with stainless steel or nylon-coated replacement lines. Do not use tape or sealant on fuel lines - full section replacement is required. Cost is $200-$500 at an independent shop.
Sources for this issue (2)
Toyota Corolla · 2000–2008
Corollas in the 8th- and 9th-generation range (2000-2008) commonly develop EVAP system faults from a failing charcoal canister, stuck vent valve, or related vacuum switching valve problems. Owners typically report a persistent check engine light with no major drivability issue, but the vehicle fails emissions inspection and may be difficult to refuel if the vent path is restricted. Toyota service literature and repair databases frequently reference canister-related EVAP diagnosis on these years.
Common Symptoms
- check engine light on
- emissions test failure
- difficulty filling fuel tank
- fuel nozzle clicks off repeatedly
- stored EVAP leak or vent codes
How to Fix
Diagnosis involves smoke-testing the EVAP system, checking vent valve operation, inspecting hoses for cracks, and verifying purge and canister switching valves. Depending on the exact failure, repair may involve replacing the charcoal canister assembly, vent valve, or damaged hoses, then clearing codes and confirming the EVAP monitor completes normally.
What you need to fix it
Only diagnosis- and fitment-reviewed repair parts are linked here.
- Toyota 77740-02102 genuine charcoal canister assembly
confirmed leaking or functionally failed early-generation canister Fitment/availability: 2000-2002 Toyota Corolla catalog branch; replaces 77740-02100 and 77740-02101; confirm VIN and emissions equipment Fitment/availability: Ships in 1-…
- Toyota 77740-02121 genuine charcoal canister assembly
confirmed failed early ninth-generation canister Fitment/availability: 2003-2005 Toyota Corolla catalog branch, generally the early production split through approximately May 2004; exact build date and VIN required Fitment/availability: …
- Toyota 77740-02130 genuine charcoal canister assembly
confirmed failed later ninth-generation canister Fitment/availability: 2004-2013 Toyota Corolla catalog branch; use here only for the issue's later 2004-2008 production and confirm build date and VIN Fitment/availability: Add to Cart liv…
As an Amazon Associate, we earn from qualifying purchases; other part links may also earn au7o a commission. Confirm fitment by VIN before buying.
Sources for this issue (2)
Saturn Aura · 2007–2009
Volkswagen Golf R · 2015–2022
Find P0442 by make
Browse every documented model and issue for your make.
P0442 code reference
General diagnostic-code context. The code alone does not confirm a cause for your vehicle; use the applicable issue card and its sources.
Frequently asked questions
What does P0442 mean?
P0442 stands for "Evaporative Emission Control System Leak Detected (Small Leak)." This emissions code means the evaporative emission (EVAP) control system has detected a small leak. The EVAP system seals the fuel tank and captures gasoline vapors, routing them to be burned in the engine instead of escaping into the air, and the computer periodically pressure- or vacuum-tests the system to confirm it's sealed. A small leak the size of about a 0.040-inch hole will set this code. By far the most common and cheapest cause is a loose, damaged, or missing gas cap, so that's the first thing to check, though any cracked hose or worn seal in the system can also trigger it.
What are the most common causes of P0442?
The most common causes of P0442 are: Loose, damaged, or missing fuel filler cap, Worn or cracked gas cap seal, Cracked or disconnected EVAP hose or line, Faulty purge valve or vent valve, Damaged O-ring or seal at the fuel tank or filler neck, Small crack in the charcoal canister, Leaking fuel tank sending unit gasket. The specific cause varies by vehicle.
How much does it cost to fix P0442?
Repair costs for P0442 range from $20 to $900, depending on the vehicle and root cause.
Which vehicles are affected by P0442?
Au7o has documented P0442 across 32 vehicle models from 15 manufacturers: Chevrolet, Ford, GMC, Honda, Hyundai, Infiniti, Jeep, Kia, Mazda, Nissan, Pontiac, Saturn, Subaru, Toyota, Volkswagen.
Join 700+ subscribers following Au7o for vehicle insights and updates.
Content compiled with AI assistance using NHTSA complaints, TSBs, and owner reports. May contain errors. Always verify with your vehicle's service manual.