What does code P0455 mean on a Cadillac and is it safe to drive?
P0455: Evaporative Emission System Leak Detected (Large Leak). Here's what it means on your Cadillac, what usually causes it, what repairs typically cost, and how safe it is to keep driving.
What this code means
A large leak has been detected in the EVAP system. Could be gas cap left off, disconnected hose, or damaged canister.
Common causes for your Cadillac
- Gas cap missing or not sealed
- Disconnected or ruptured EVAP hose
- Damaged charcoal canister
- Faulty purge/vent solenoid
Symptoms
- Check Engine Light
- Fuel smell possible
Typical fixes
- Install or replace gas cap
- Inspect and repair EVAP hoses
- Replace canister or valves as needed
Repair cost range
For a Cadillac, repairs for P0455 often fall between $20 and $500, depending on the cause and whether you use OEM or aftermarket parts. Labor rates vary by location.
Known issues on Cadillac
Cadillac P0455 follows the GM EVAP pattern. Start with the gas cap; if clear, the EVAP vent solenoid near the fuel tank is the most common hardware failure on SRX and XT5 platforms.
Most commonly affected models