How much does it cost to fix P0442 on a Ford?

Repair costs for P0442 on Ford vehicles typically range from $40 to $280 depending on the underlying cause. The most common fix is: Loose, cracked, or worn gas cap seal failing to hold proper vacuum in the EVAP system..

Ford Check Engine Code

P0442 on Ford

Evaporative Emission Control System Leak Detected (Small Leak)

Severity: low DIY difficulty: 1/5 Ford cost: $40–$280

Last updated April 30, 2026 Also covers: Lincoln, Mercury

P0442 on Ford: what makes it different

A small/medium EVAP leak code is very common on Ford models due to the plastic fuel filler necks and gas caps used across many trucks and SUVs, which develop tiny leaks or seal wear over time.

Most-affected engines

EcoBoost 1.5L/2.0L/2.7L (Escape, Edge, F-150)
Duratec 2.5L/3.5L (Fusion, Edge)
Coyote 5.0L V8 (F-150, Mustang)

Common model years: 2011–2020

Most likely cause on Ford

Loose, cracked, or worn gas cap seal failing to hold proper vacuum in the EVAP system.

Known Ford engine-family issues

Many Ford trucks and SUVs route EVAP lines along the frame rail near the fuel tank, where road salt and debris can cause small leaks over years of use — this is a frequent reason P0442 reappears after a gas cap replacement doesn't fully fix it.

Ford-specific causes (most common first)

Gas cap not tightened fully or seal degraded from age/UV exposure
Small crack in the plastic fuel filler neck or filler pipe hose
Cracked or disconnected EVAP purge/vent line, common on trucks with underbody routing
Charcoal canister vent valve stuck slightly open
Fuel tank pressure sensor giving a false small-leak reading
Aging rubber seals at the EVAP canister purge valve connection

Ford-specific diagnostic tip

Start with the gas cap: inspect the seal for cracking and make sure it clicks fully when tightened, since this resolves a large share of Ford P0442 cases before any smoke-test diagnosis is needed.

Symptoms drivers report

Check engine light
No drivability issues

Typical repair cost on Ford

Most Ford owners fix P0442 for between $40 and $280, depending on which underlying cause turns out to be at fault. Start with the most-likely cause for your vehicle — Loose, cracked, or worn gas cap seal failing to hold proper vacuum in the EVAP system. — before throwing parts at it.

Ford P0442 FAQ

Can a loose gas cap really trigger P0442 on a Ford?

Yes, it's one of the most common causes — Ford's EVAP system is sensitive to small vacuum losses, and a loose or worn cap seal is often enough to set this code.

Why does the code come back after I replace the gas cap?

If the leak is elsewhere, like a cracked filler neck or EVAP hose near the frame rail, the code will return; a smoke test is the best way to pinpoint it.

Is P0442 urgent to fix on a Ford truck?

It won't cause drivability issues, but it will likely fail an emissions test and can sometimes point to a leak that worsens over time, so it's worth diagnosing within a reasonable timeframe.