What does code P0455 mean on a Porsche and is it safe to drive?
P0455: Evaporative Emission System Leak Detected (Large Leak). Here's what it means on your Porsche, what usually causes it, what repairs typically cost, and how safe it is to keep driving.
PowertrainMedium urgency
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 Porsche
- 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 Porsche, 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 Porsche
Porsche P0455 large EVAP leak—gas cap seal degradation is common given the large-volume filler neck on Cayenne and Panamera. If the cap is correct, the EVAP purge valve (shared VW Group N80 design) is the next suspect.
Most commonly affected models
Cayenne 2011–2018Panamera 2010–2016Macan 2015–2023