Q: What's the best way to check for Evap small leak. I'm getting code P0442

asked by on August 15, 2016

I'm getting that code and wondering what is the best way to find the leak to fix it

My car has 131000 miles.
My car has an automatic transmission.

P0442 indicates that you have a small leak in the evaporative emission system. Many times this is caused by a loose or faulty fuel cap. Make sure that the cap is tight and in good condition, so that it seals completely.

If it is a cracked hose or faulty valve, a smoke test can be used to find the leak. Basically, it fills the system with a non-reactive smoke under a small amount of pressure. Any leaks in the system will be evident by smoke escaping through the location of the leak. If you would like this done for you, a certified technician, like one from YourMechanic, will be able to detect the leak for you and make the appropriate repair.

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