Volkswagen Repair: 02Passat check engine light, crankcase breather hose, evaporative emissions

Question
Hi I just recently purchased a 2002 Passat with 42,000 miles.  I need to smog the car, but before I could the check engine light came on, so I went and had a diagnostic, the code was a P0442 (EVAP system small leak detected)they cleared the code and then the light came back on and what do you know it was the same code again, now I do not know what to do.  I am taking it in tomorrow for a recall, they are replacing the crankcase breather hose.  Do you think that the leak problem is related??  I did notice that in the old paper work from the previous owner, that there was a code for a gross leak and something about running to lean.  Do you think that these repairs are going to be expensive??  I know nothing about cars and seem to always get taken advantage of,( I just did the 40k maitenence and they did nothing) so I want to go there with a little bit of confidence from you knowledge :) Thank you!!

Answer
Hi Stacie;
I'm sorry to hear about your past, negative experiences.  Unfortunately, there are a number of things about Volkswagens that are unique, and can be a source of pride, or a source of frustration.  My shop manager sees all of these things as "opportunities" to make money, and unfortunately, sometimes, gouge the customer.  I hope that I can be accurate enough to save you from my managers' type of personality.  My shop foreman is the fellow who gains a sense of pride from Volkswagen ownership, and uniqueness.  Now to the question at hand.  Usually, a small leak in the EVAP(evaporative emissions control system), is something simple like a loose gascap, a clogged, or leaky "N80" valve(yeah, I know, both...leaky, or clogged, and additionally the signal to the N80 valve may be corrupted at the ECM...(very, very, very rare, but it can, and sometimes does happen.  I hope you are beginning to sense some of where I am going with this.  Without a hands on experience to help with the diagnosis, I can't say for sure what is causing a "small leak."  However, there is one more common possibility, and that is the tubing that contains the gasoline vapors, and keeps them from escaping into the atmosphere, and polluting with unburned hydrocarbons, could be cracked.  I've even seen the vapors escaping from the electrical "pressure sensing" connector in the piping itself.  There is a machine used to expose the leak called a "smoke machine."  It uses Nitrogen gas(inert, in this case), and a special light oil like "3-in-1," or "WD40," or something similar in a pressure vessel that is vented through the EVAP system of the car.  A white "smoke" is produced when this chemical suspension comes in contact with the air.  Once you see the smoke, you know where the leak is.

You know it might be just this simple:  It might just be the gas cap itself.  Sometimes they leak after 400, or 500 uses.

Please forgive me going on, and on.  I really love this stuff, and sometimes I get way too verbose about the emissions controls, especially.  They are the places where the problem is a puzzle, and the solution is ALWAYS "simple," and (in some very few cases) "elegant."

I sense that you too, are elegant.  I will leave it at that.

Good luck, Stacie..I hope you feel confident, and poised when you go to the local dealer and say.."I heard it could be the 'N80' valve, 'What does the technician say?'"  Personally, I hope it's just the gas cap.