Skip the auto shop - Our mechanics make house calls

Q: P0442-EVAP System leak detected

asked by on

My car won't pass a smog check due to a P0442-EVAP System leak detected.

Hi. The evaporative emissions (EVAP) system is used to prevent fuel vapor from escaping into the atmosphere. Code P0442 stands for EVAP system small leak detected. The cause of this code can be difficult to diagnose. It could be triggered by a tiny leak the size of a pinprick. A trained technician will use an EVAP leak detector to find the source. This device puts smoke in the system to reveal the leak.

Was this answer helpful?

Need advice from certified mechanic? Get help now!

Over 1000 mechanics are ready to answer your question.
The statements expressed above are only for informational purposes and should be independently verified. Please see our terms of service for more details

Ask a Mechanic
(100% Free)

Have a car question? Get free advice from our top-rated mechanics.

Ask A Mechanic
Over 10,000 questions answered!

Get an instant quote for your car

Our certified mechanics come to you ・Backed by 12-month, 12,000-mile guarantee・Fair and transparent pricing

Get a quote

What others are asking

Q: Have replaced power steering pump three times. Works well for about a day and then stops. There is no leaks.

Hi there. The issue is not the pump. The pump will fail if the power steering control valve sticks and stops working. The power steering control valve is located in the rack and pinion steering system. If you need further...

Q: What precautions should I observe when driving?

Getting out on the road is the entire point of owning a vehicle. However, you need to ensure that you’re doing it correctly. If you’re unfamiliar with the controls in the car, or you’re not using the right driving techniques,...

Q: Check engine light is on, need help with codes

What is most likely happening is that you have a small vacuum leak somewhere. There are many small vacuum lines in the emissions control system. I would recommend having a mechanic who is proficient in emissions diagnostics take a...

Related articles

P0052 OBD-II Trouble Code: HO2S Heater Control Circuit High (Bank 2 Sensor 1)
P0052 code definition HO2S Heater Control Circuit High (Bank 2 Sensor 1) What the...
How to Avoid Back Pain in a Car
If you have back problems, sitting in a car for an extended period of time can be excruciating. Even without back problems, you could experience discomfort and soreness from...
P2428 OBD-II Trouble Code: Exhaust Gas Temperature Too High Bank 1
P2428 code definition A P2428 trouble code signifies that the PCM has detected a problem in the exhaust gas temperature sensor circuit in bank 1, which subsequently contains the number one...