OBD · Emissions control

P0456 EVAP system very small leak detected

Monitor

What this code means

P0456 is a generic OBD code shared by all manufacturers since 2001 for petrol and 2004 for diesel. It relates to: emissions control. The code tells you what the ECU measured as abnormal, not necessarily which part to replace.

Severity: Monitor. You can drive normally but get it checked in the coming weeks. It may fail an MOT or roadworthiness test.

Most common causes

This code has too many model-specific causes to rank reliably. A scan with your symptoms narrows it down.

How to read this code

An OBD scanner plugged into the 16-pin socket under the steering wheel reads and clears codes. Bluetooth models cost £20 to £40. Clearing a code without fixing the fault is pointless: it comes back.

Frequently asked questions

What does code P0456 mean?

P0456: EVAP system very small leak detected. P0456 is a generic OBD code shared by all manufacturers since 2001 for petrol and 2004 for diesel. It relates to: emissions control. The code tells you what the ECU measured as abnormal, not necessarily which part to replace.

Can I drive with code P0456?

Monitor. You can drive normally but get it checked in the coming weeks. It may fail an MOT or roadworthiness test.

How to read this code

An OBD scanner plugged into the 16-pin socket under the steering wheel reads and clears codes. Bluetooth models cost £20 to £40. Clearing a code without fixing the fault is pointless: it comes back.