Every so often my SES will come on with the gas cap code. It comes on in weird intervals. I always twist the gas cap more than far enough. I cleared the code two weeks ago, and then a month ago before that. My buddy has the OBDII scanner and I hate always asking him to use it. Will un hooking the battery clear the SES trouble code or is the scanner my only option?

Today, I got off the highway, came down the a red light, then it came on. I figured the gas cap would have been checked when the car starts up.

And if taking power away would clear it... would my better bet be disconnecting the battery terminal or taking the wire harness off the PCM? and how long should i wait?

This may be related, but when I fill up with gas, i can smell it until I drive about 50 miles, so I am thinking that maybe the purge valve back there is stuck open. Can someone point me in the right direction?

The system makes its checks at various intervals. I chased that code around for a few months on my friend'* 2000 SSEi. I'd try something, and it would go away for week or two, then come back on.

First, if you top off the tank on a fill up, it can cause the gas smell. With the charcoal cannister under the car, under the back seat, it is more susceptible to getting filled with vapors, or gas if you over fill.

What I finally tracked the problem down to was the vent valve by the rear tire not sealing properly. More information on that in this thread.
http://www.bonnevilleclub.com/forum/...86302&start=20

Thanks that would make sense. If the vent wasn't sealing properly the pressure could be reading differently and tripping the SES.

Is there any other way to clear the trouble code?

Disconnecting the battery will not clear it. You need either a code reader, or scanner with that capability, or you may be able to talk someone at Advance or Autozone into clearing it. Some won't do it. Other than that, after a certain number of tests (30-40 I think) without a problem, it will eventually go off by itself.

Yeah it said 40 correct ignition cycles.

Thanks Archon, I'll just ask my buddy for his. This weekend I will clean that vent solenoid.
Does anyone have any pictures of it under the car... I looked before and I wasn't sure which box it was. Thanks guys.

I don't have any pictures of it, other than the diagram that was posted in the other link. Just follow the evap lines back from the cannister. It'* a small black box, roughly the size of a deck of cards. Seems to me the diagram would indicate it on the passenger side, but I believe I found it on the drivers side.

you don't have any Autozone'* in Edinboro, PA?

there are some in erie pa, but they don't always like to delete the trouble codes. I am just going to use my friend'*.

If I smell gas near the rear of the vehicle...what are all the possibilities?

I will get and code checked tonight... but I am assuming it'* the P0440 again. If it was the purge valve not sealing, wouldn't the P0442 code come up for small leak detected?