p0455
Moderate
Cadillac · Sedans
Evaporative Emission Control System Leak Detected (Large)
Quick Answer
Error code P0455 on your Cadillac Sedans means: Evaporative Emission Control System Leak Detected (Large). This is usually fixable — see the step-by-step guide below.
Affected Models
Likely Causes
How to Fix It
1
Check fuel cap for damage or loose fit
2
Inspect fuel tank for cracks or damage
3
Check all vapor hose connections
4
Perform smoke test to locate leak source
5
Repair or replace leaking component
Pro Tip
This fix requires some technical knowledge. If you're unsure about any step, consider contacting support or a qualified technician.
Parts You May Need
Fuel cap
Fuel tank repair kit
Vacuum hose
Smoke machine
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