So i've had my car about three weeks now, and this morning my dreaded check engine light comes on.


I got it checked at advance, it came up with a P0442 EVAP emissions leak..i have no idea what this is. I know the car has a loose exhaust pipe that needs to be fixed, it rattles.

My brother said it is probably an exhaust gasket, but my car doesn't sound like it has a leak. Unless that uber sexy popping noise it makes when you let out of the throttle is one, if it is i will be upset haha.

My question is, does anyone know what this code is? anyone have any past experience with it? Thanks.

 

Check your gas cap. EVAP has nothing to do with your exhaust.

 

I did, it's tight. You know how the 99s are, one click and thats all you get.


Could it just be faulty? should I get a new one?

 

K there is 3 things you can do:

Take the gas cap off and reinstall. clear the code and see if it comes back on.
Get a new gas cap.
Check the EVAP system for cuts/holes in the hoses.

The EVAP system prevents gas vapors from escaping, it holds the vapors in a canister until the engine is running and purge control valve opens and releases the vapors into the engine.

 

This indicates a fuel vapor leak in the EVAP control system. It means a very small leak has been detected. In fact, the leak can be from a hole as small as 0.04" in diameter. The (EVAP) emission control system prevents the escape of fuel vapors from a vehicle's fuel system. Fuel vapors are routed by hoses to a charcoal canister for storage. Later, when the engine is running a purge control valve opens allowing intake vacuum to siphon the fuel vapors into the engine.



SymptomsYou likely won't notice any drivability problems.

CausesA code P0442 most likely means one or more of the following has happened:

•A loose or improperly affixed gas cap
•A non-conforming gas cap (i.e. not factory/original brand)
•A small leak/hole in a fuel vapor hose/tube
•Other small leak in EVAP system
•Faulty vent o-ring seal
Possible SolutionsWith a P0442, the most common repair is to:

•Remove and reinstall the gas cap, clear the codes, and drive for a day and see if the codes come back.
•Otherwise, replace the gas cap, or
•Inspect the EVAP system for cuts/holes in tubes/hoses

have the codes cleared after you reinstall the gas cap. if this does nt fix it i would recomend doing a smoke test on the evap system to find out where the leak is. since its a small leak you will never see a pinhole with the naked eye but with a smoke machine you can pick up where its leaking at pretty quick

 

Thanks alot, you guys are a big help! When I put my car in the shop on Monday I will clear the codes and reinstall the cap while i'm changing the oil. If it doesn't work I guess it will be taken to an auto shop which has a smoke machine.

 

It's most likely a gas cap leak, it's not too uncommon.

 

I just bought a new one from advance, I hope it works. ill put it on tomorrow

 

DId you buy the regular cap or the locking one? The locking caps tend to fail, like mine did so I had to go back with a stocker.

 

You're better off buying a new gas cap from the ford dealership cause most of these other gas caps that you can buy from auto part stores don't work. Believe me cause I had one and it didn't fit right for my 01' Mustang. I just got mine fixed today, so hopefully the engine light won't come back on anymore. I also had an exhaust leak.