Code P0440?

Yes the light will come on when first started because it meets the evap test parameters. Did you put on a ftermarket gas cap?I have seen people use the aftermarket caps on those vues and that be the cause of the P0440. Especially when using a locking gas cap. When they checked for leaks did they do a nitrogen leak check watching the flow meter. Then do a smoke test looking for leaks?I always do it that way to double check there isnt a active leak at the time I tested it.

As far as the cap goes I have seen aftermarket gas caps intermintantly set that code I would hate to rule that out then go chasing your tail on something else when it was a simpe gas cap all along. Also what size engine do you have?I will do some checking on bulletines etc after you tell me your engine size.

Just to be sure your setting a P0442 not a P0440 correct?Because there is no code P0440 for that vue I was assuming you ment P0442 all this time and just want to make sure iam correct. Also a aftermarket cap can cause a intermintant evap code set and pass the smoke test and nitrogen test.I have seen that before the first time I ran across it that really thru me for a loop wasting my time trying to track down a problem that was staring me right in the face. Also there is two ways to test with smoke and nitrogen as far as getting it in the system one way is to hook the smoke nitrogen cart to the evap test port. The other way is to have a adapter to hook it to the fuel filler neck. Thats another way the cap tests results can be skewed. If you hook the machine to the evap test port you are actually testing the cap on the actual fuel fill neck. If you use the fuel filler neck adapter then you are testing the cap on the the test adapter and not the actual fuel filler neck that the cap is normally on. So there are a few varibles here I also always test both methods myself just to cover all the varibles and my bases.

A bad gas cap can cause a small leak code if the cap is missing or loose you would set a large leak code.I posted a bulletin about setting that codes but you would see smoke leaking from the canister but worth a look. If you have a clogg or restriction stopping the vacuum from getting to the gas tank and the fuel pressure sensor to read the vacuum then it could sett a code. Its easy to see if there is a restriction. Unhook the evap hoses and see if you can easly blow there the lines canister etc. Its going to be hard t diagnose without atleast a smoke machine.I have seen intermintant leaks cause by fuel filler neck fuel pump module seals all kinds of crazy things.

Keep me posted even though he cleared the code everytime the code is cleared it resets the monitord O2 sensor egr evap cat etc so after you fix the problem you have to relearn the monitors before you get it smogged or it will fail for the monitors not being ready. Keep me posted and we will try to figure this out one way or another.