Hello everyone. I want to say first I am not very mechanically inclined, or maybe not at all. My check engine light came on so I went to Advanced Auto Parts to have the guy hook up the machine to tell me what was wrong. It was code P0442 (Emissions Control System Leak). I have a couple questions about this. First off is it a major problem? Secondly is this going to expensive to fix? And lastly and I capable of fixing it myself. I have the Haynes Repair Manual. I don't totally understand what it says in there. I have read some other posts on here. I have seen that maybe taking my gas cap off and putting it back on could fix it? Some other things about the oxygen sensor? Not real sure. If anybody could give me advice on if I'm capable of fixing this or should I take it to someone who knows what they are doing? Thanks for any help

 

Start with this:
P0442 Explained

The most common cause of this problem is an improperly tightened gas cap. If you refueled recently, when you tightened the cap, you need to tighten it until it clicks at least 3 times. If not, it may leak during the evaporative emissions test. This code can also be caused by a faulty gas cap, a faulty vent solenoid, or a few other things. Run a search for P0440 and you should turn up more causes.