P0496: EVAP system high purge flow
The engine draws vapour from the tank when it should not, nearly always because the purge valve is stuck open. Starting after refuelling may suffer.
| Code | P0496 |
|---|---|
| System | Engine and transmission |
| Group | P04xx, Emissions control |
| Type | Generic: it means the same on every make |
| Can you keep driving? | With care |
What P0496 means
The purge valve should only open at certain times so the engine burns the vapour stored in the canister. The ECU sees more vacuum or vapour flowing than expected, even when the valve is told to close. Most often the valve is stuck open.
Most common causes
- Purge valve stuck open or not closing fully
- Purge valve hoses swapped over after a repair
- Canister soaked with fuel from topping up past the pump’s first click-off
- EVAP pressure sensor giving a false reading
Symptoms
- Hard starting straight after refuelling
- Rough idle or stalling when cold
- Engine warning light on
- Sometimes a smell of petrol
Can you drive with P0496?
With care You can drive, but the idle may suffer and the canister can be ruined if liquid fuel gets in. Get it fixed soon and stop filling up after the first click.
Open the bonnetthe in-depth explanation
How to check it
With the engine off, disconnect the purge valve hose on the engine side and blow through it: with no power to the valve, no air should pass. And stop filling the tank when the pump first clicks off.
How to read and clear P0496 with Final OBD
Plug an OBD2 scanner in under the steering wheel, switch the ignition on and open Final OBD. Under Faults you’ll see P0496 with its description and whether it’s confirmed, pending or permanent.
If the engine stores it over standard OBD, with FREE you read this code with its explanation for nothing and clear it. With PRO you also read the faults of every control unit and clear them in all of them.
Clearing the code only turns the light off: if the cause is still there, it comes back. Clear it once it’s fixed, and not right before an inspection. It’s all in how to read and clear fault codes and in inspections and OBD.
Similar codes
- P0492 Secondary air injection system insufficient flow (bank 2)
- P0493 The coolant fan runs too fast because its clutch is locked
- P0494 The radiator fan is turning slower than it should
- P0495 The fan speed is above normal
- P0497 EVAP system low purge flow
- P0498 The evaporative emission system vent control gives a lower signal than normal
- P0499 The evaporative emission system vent control gives a higher signal than normal
- P049A There is a fault in the exhaust gas recirculation B flow
- P0400 Exhaust gas recirculation (EGR) flow malfunction
- P0401 Exhaust gas recirculation (EGR) flow insufficient
- P0402 Exhaust gas recirculation (EGR) flow excessive
- P0403 EGR control circuit malfunction
What does code P0496 mean?
The purge valve should only open at certain times so the engine burns the vapour stored in the canister. The ECU sees more vacuum or vapour flowing than expected, even when the valve is told to close. Most often the valve is stuck open.
Can you drive with P0496?
You can drive, but the idle may suffer and the canister can be ruined if liquid fuel gets in. Get it fixed soon and stop filling up after the first click.
How do you clear P0496?
With an OBD2 scanner and an app like Final OBD, which clears it for free if it’s stored by the engine control unit. But clearing it only turns the light off: if the cause isn’t fixed, P0496 comes back.
Read it on your car
Final OBD reads and clears engine faults through standard OBD for free, each one explained in plain English. With PRO it also reads the faults of every control unit, each make’s own codes included, and clears them in all of them.
