EVAP gross leak on Toyota — fuel cap and vacuum switching valve on Corolla/Yaris/Auris.
Toyota P0455 — EVAP gross leak on Toyota — fuel cap and vacuum switching valve on Corolla/Yaris/Auris. Typical UK independent garage cost: £20–£280.
What actually causes P0455 on a Toyota
Toyota P0455 is fuel cap or VSV (vacuum switching valve). Hybrid Toyotas have a sealed EVAP system that's pressure-monitored differently — diagnostic procedure differs.
Toyota engines that log P0455
- Corolla/Auris 1.3/1.6/1.8
- Yaris hybrid 1.5
- Prius 1.8 hybrid
How we diagnose P0455 on a Toyota
- Fuel cap test/replace
- VSV resistance test
- Smoke-test EVAP
- Use Toyota-spec scan tool on hybrid
The common misdiagnosis to avoid
Hybrid Prius P0455 needs Techstream-style diagnostic — generic OBD-II won't drive the EVAP self-test correctly.
Toyota P0455 repair cost in the UK
Expect £20–£280 including parts and labour at an independent garage. Main-dealer quotes on Toyota are usually higher for the same job, and the spread exists because the cheap cause and the expensive cause throw the same code — pay for the diagnosis before you pay for parts.
Bob's workshop tip
Prius P0455 — Techstream or no diagnosis. Don't waste time on generic scanners.
Codes usually seen alongside P0455 on Toyota
- P0441
- P0456
Symptoms drivers report with P0455
- Engine warning light appears within a mile of filling up — sometimes the cap wasn't clicked shut
- Strong smell of petrol vapour around the car after parking on a hot day
- MPG barely affected — you'll only notice on the fuel receipts over a month
- MOT emissions test passes but the MIL means an MOT visual fail on any car registered 2018+
- Paired codes: P0440 (generic EVAP), P0441 (purge flow), P0446 (vent circuit), P0455 keeps returning
- On Toyota hybrids: MIL flashes then goes steady — hybrid pressurised system is very sensitive
Repairs that clear P0455
- Refit fuel cap
- Inspect hoses
For the generic, all-makes explanation of this code — meaning, every known cause and UK cost bands — see our P0455 guide.