After buying the " Autoenginuity Scantool" (loving it) and having cleared code: (Vechile Speed Idle Control - P440 - Evaporative Emmission Control System) four times in the last two months perhaps it is time to find out why it keeps coming back!!! The code disappears for days or even weeks after being cleared. I'm wondering if it has something to do my check gas cap that I have had problems with since I bought the car. I have tried every trick mentioned on this website to get rid of the problem. Including having the dealer install a new gas cap, smoke test on evap system, pressure test on system, and cleaned the filler neck to ensure sealing was taking place. The P 440 code did show up on the dealers work order when I had the above problem checked so that is why I wonder if there is a connection? Any suggestions would be greatly appreciated. [/code]

the pcm tests for a leak in the EVAP system by:

Electrically closing the vent valve in order to seal the system.
Electrically opening the purge valve which allows the running engine to draw a vacuum on the fuel tank.
The pcm then closes the purge valve, resealing the system.
The pcm then monitors the fuel tank pressure sensor and determines:
;If vacuum was achieved.
;If a leak is present, how large the leak is.
;If vacuum was not achieved.
If one of the above tests fails, the pcm remembers that the system failed the test.
If the pcm sees a failure of the EVAP test for two consecutive tests, the module will set a trouble code for EVAP leak (DTCs P0440, P0442, or P0446).

Judging by your reply and all the tests that have been done could it have something to do with my filler nozzle having a leak of some sort??

There are a lot of parts that make the evap system and they sure are a pain. You have the new cap and have run several tests with the dealer, it comes and goes about twice a month.
Does the code show up after you fill up or soon after?
Might be a sticky purge valve, or vent valve?
Do you get any other codes or just the 440?

For the last few days I have been reading manuals on this evap system and all the quirks that can go wrong. I'm amazed other than check gas cap message, after 108,000 miles on my 2k that I have not had a problem. And I still have the original cap

There is a charcol filter for the gas fumes, if this gets saturated with gas, and this can happen when you over fill, you can set an evap dtc if the car is started twice with this condition.

Is your gas gauge working?

I'm sorry I've been away for a couple of days. Some quick answers to the questions asked:
Do I get other codes than P440?
No the only code I get is the P440.

Is it the purge valve or vent valve?
I have not considered that but is it something I can fix myself or does it need special equipment or more aptitude or ability than a do it yourselver.

Charcoal filter saturated?
I do not overfill or at least I have not for at least the last couple of months. Where is this filter in the gas cap? or somewhere in the nozzle?

Gas guage working?
Unfortunately it can find full and empty way way too often!! The amount of gas required to fill it up matches capacity and what the gas guage is calling for.

Thanks again for trying to help me solve this. My check engine light just came on again today. This time it is half a tank and only a couple of days since I cleared the code.

The main problem here murwen is access. And the fact that the only code is 440 tells me the problem exists most of the time as you need two failures in a row to get the code.

You would need a shop manual to take this on, I'm going to go back and reread for something obvious but I doubt its there?

I do believe my next purchase will be a shop manual. Has anyone used the computer online version of the manual such as ALL DATA for $29.00 a year. Makes sense if it is any good. By the time I pay for a written shop manual hopefully I've upgraded to newer model.

I figured out mine is setting cause the gauge and DIC do not agree and it gets confused for pressure needed to test. My gauge reads full or empty. The DIC is correct though.