OBD · Emissions control
P0442 EVAP system small leak detected
What this code means
P0442 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.
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 P0442 mean?
P0442: EVAP system small leak detected. P0442 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 P0442?
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.