2024 Buick Encore GX P0455: Large EVAP Leak — Warranty Guide

P0455 on Your 2024 Buick Encore GX

A P0455 on your 2024 Encore GX means a large EVAP leak. The refreshed subcompact luxury SUV is fully under Buick warranty. Gas cap first.

Symptoms

• Check engine light with P0455
• Possible fuel smell
• Gas cap not seating
• EVAP monitor incomplete

Top Causes

1. Gas Cap Seal (Very High Likelihood): Loose or factory defect. Warranty-covered.
2. EVAP Vent Solenoid (Medium Likelihood): GM vent valve. Warranty-covered.
3. Purge Valve (Medium Likelihood): Factory defect. Warranty-covered.
4. EVAP Canister (Low Likelihood): Manufacturing issue. Warranty-covered.
5. Software Calibration (Low Likelihood): ECM update. Warranty-covered.

What to Do

Tighten the gas cap and drive 2–3 days. If P0455 persists, your Buick dealer will diagnose and repair free under warranty.

Warranty

Your 2024 Encore GX is covered by Buick's 4-year/50,000-mile warranty through 2028. Federal emissions (8yr/80k) extends through 2032.

Safe to Drive?

Yes. P0455 doesn't affect the turbo engine, AWD, or any features.

Frequently Asked Questions