P0442, What do I do to correct this?

[SOU812]

Hello everyone,
First off, please excuse me if I screw this up. It's first time using a forum.
Anyway, I own a 2004 Neon SXT with a little over 43,000 miles on it, I just got a check engine code of P0442 "evap leak monitor 0.040 leak detected in the evaporative system. What is this, and how do I fix it? Not mechanically inclined, can change the oil and plugs but, that's about it.

Any response would be greatly appreciated.

Troy Choina

[rice_eater]

I believe its referring to the evap purge solenoid. It should be on the passenger side of your engine compartment. All it does is regulate vapors and pressure in your fuel system. A "leak" just means somewhere in the system there is a loose line, or your gas cap is not tightened all the way. I'd start by checking the gas cap if I were you, as its easiest, but if that doesnt fix the problem you'll have to check the vacuum lines attached to the solenoid, and possibly elsewhere in the fuel system.

I've never had problems with my evap system, so I dont know much about it. dodgeneonACR98, n-gin, RadarLove, or HoodooGuru might know more about it, or if theres anything specific to the 2nd Gen neons vs the 1st Gen. Good luck.

[SOU812]

Thanks for quick reply. I was thinking about the gas cap, since I put a generic "locking cap" on it about a month ago.Had problem with someone syphoning gas. But would it take that long to get the error.

Troy Choina

[dodgeneonACR98]

Welcome to DT. And I am sorry to hear that your gas is getting syphoned out, that must suck!!!!!!! Some people are just not right! I have a couple of solutions for that! :IDEA:
You could always tie a pit bull to the car!!!!! :D
Or you can do what Id do and that is........Get a 5 gallon gas can and add as much sugar to it as you can without leaving it sitting in the bottom. Sit the can beside the car then wait to see who's car starts smokeing!!!!!! :D :D

It may have to do with the gas cap like Rice_Eater said. That would be my first guess too. Maybe the new one isnt all that great and leaks a bit.

If I were you I would reset the PCM by pulling the Fuel pump fuse and relay to clear the code, Install the old cap and see what happens. Just when you park it at night you might want to install the locker cap. Good Luck

[rice_eater]

Switching caps everynight would be a major pain in the behind... I doubt your problem has to do with the differnent cap. I would still check the cap and make sure you have it on tight, but there should be no difference between a locking cap and the stock cap. Resetting the PCM like ACR98 said is a good idea as well, it may just be a fluke code.

[hemi1569]

A .040 is considered a Large leak. The first thing to do is to make sure your car is completely warmed up, and while it is idling, go back and sniff the gas cap. If you smell vapors, replace it. If you don't, check all lines from your purge solenoid back, remember even a slight crack in a vacuum line means immediate replacement. If you have access to a lift or even car ramps, that would help. Usually it is a leak at the LDP leak detection pump hose. A gas cap will throw a medium to large leak(.040) sometimes though. A .020 is considered a small leak and is USUALLY a gas cap but any lines you see that are dry rotted in the slightest MUST be repaired. You can use vaccum hose from the local parts store to same money. Check the lines all the way down the framerail and try to look up by the gas tank. A large leak will not necessarily mean you will be able to smell it while it is running, but you may be able to.

[SOU812]

Thanks for the help, I'll have to make time and check it before it gets any worse.

Troy Choina

[SOU812]

Thanks for reply,

I'm going to put original cap back on car. and have to clear junk out of garage so I can put both cars in.

Troy Choina
Owner/Operator
Full Force Powder Coating :)

[SOU812]

Thanks for reply,

I'm putting original cap back on and clearing out garage so I can put both cars inside.

Troy Choina

[dodgeneonACR98]

I'm putting original cap back on and clearing out garage so I can put both cars inside.


That sounds like a plan! Remember to clear your codes when you change the cap. If it comes back you more than likely have a leak.