P0455 Code: 2020 Chevrolet – What It Means & Cost to Fix

2020 Chevrolet Camaro P0455: Large EVAP Leak Causes

Solving P0455 on Your 2020 Chevrolet Camaro

A P0455 on your 2020 Camaro means the ECM detected a large EVAP leak. Your 6th-generation Camaro—whether it's the 2.0L turbo, 3.6L V6, 6.2L V8 SS, or supercharged ZL1—is out of GM's basic warranty but covered by the federal emissions warranty. Start with the gas cap.

Symptoms

  • Check engine light with P0455
  • Possible P0449 companion code
  • Faint fuel odor near the rear
  • Gas cap seal worn after 5+ years
  • Failed emissions test

Causes Ranked

  1. Gas Cap Seal (Very High Likelihood): Worn rubber seal. Replace for $10–$25.
  2. Vent Valve Solenoid (Medium Likelihood): GM's vent solenoid near the charcoal canister. $100–$200.
  3. Purge Solenoid (Medium Likelihood): Stuck open or leaking. $80–$180.
  4. Vapor Line (Low Likelihood): Cracked hose. $80–$200.
  5. Charcoal Canister (Low Likelihood): Saturated from fuel overfilling. $200–$350.

Diagnostic Path

Replace the gas cap ($10–$25), clear the code, drive 2–3 cycles. If P0455 returns, a smoke test will locate the leak. Check for companion P0449—if present, the vent valve solenoid is the cause.

Warranty Coverage

GM's basic warranty (3yr/36k) has expired. The federal emissions warranty (8yr/80k) covers EVAP through 2028. Contact your dealer.

Safe to Drive?

Yes. P0455 doesn't affect the Camaro's engine performance, handling, or any driving dynamics. Your Camaro is just as fast with P0455.

Frequently Asked Questions

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