P0442 on a 2019 Jeep Grand Cherokee

P0442 means the EVAP system could not hold pressure or vacuum during a leak test, but the leak is small.

Not your vehicle? See general P0442 info.

Most common causes on the 2019 Jeep Grand Cherokee

Ranked from 356 NHTSA owner complaints filed for this vehicle.

Sort by:

1
Intermittent, broad small EVAP leak per manufacturer TSB
Medium severity
Two owners cite the exact same manufacturer communication (wiTECH Small Leak Verification Test) for a persistent small-EVAP-leak code that dealers could not pin to a specific failed part.
Reported in 2 NHTSA complaints
2
Fuel filler/vent system malfunction causing fill/vent trouble
Medium severity
One owner reports the fuel nozzle won't stay seated during fill-up and the fuel gauge/light behaves erratically, consistent with a filler-neck seal or tank-vent path not holding properly.
Reported in 1 NHTSA complaint
Parts:fuel filler neck
3
Loose or damaged gas cap
Low severity
The most common simple trigger for this code; check the cap seal first.
Common cause
Parts:fuel cap
4
EVAP purge valve stuck or leaking
Medium severity
A purge solenoid that leaks vacuum at idle lets outside air into the EVAP system.
Common cause
Parts:purge valve
5
Cracked or brittle EVAP hose/line
Medium severity
Rubber and plastic EVAP lines harden and crack with age/heat; smoke-test to pinpoint.
Common cause
Parts:EVAP hose
6
Charcoal canister crack
Medium severity
A cracked canister housing can leak vapor and is often found during a smoke test.
Common cause
Parts:charcoal canister
7
EVAP vent valve/solenoid failure
Medium severity
A vent valve that won't fully seal keeps the system from holding vacuum/pressure during the self-test.
Common cause
Parts:vent valve

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These causes are aggregated from NHTSA owner complaints and general repair knowledge — this is not a diagnosis. P0442 on your car still needs shop confirmation before any repair.

Common symptoms

Check engine light
Fuel smell near vehicle
Usually drives normally
Hard start after fueling in some cases

What to check before replacing parts

Tighten and inspect the gas cap

Look for: A cap that doesn't click to full tightness, has a visibly cracked or flattened seal, or is simply missing is the single most common cause of a small EVAP leak — rule it out first.

Smoke-test the EVAP system

Look for: Because this is a small leak, expect only a thin wisp of smoke or a faint hiss at one spot (a hose, seam, or valve) rather than an obvious cloud — look closely and take your time.

Check purge valve sealing

Look for: A purge valve that doesn't hold vacuum when commanded closed lets a small amount of air bleed through, which the system reads as a leak during its self-test.

Inspect hoses near the tank and engine bay

Look for: Look for small cracks, soft/collapsed spots, or a hose that has pulled loose slightly at a fitting — any of these can leak just enough to trip a small-leak code without an obvious fuel smell.

Verify vent valve operation

Look for: A vent valve that doesn't seal fully when commanded closed prevents the system from holding vacuum during its self-test, which reads as a small leak even with no physical leak in the hoses.

Rather have a pro handle it? Find a vetted local mechanic.

Matching symptoms

Check Engine Light