3 engine codes

I attempted to get my '01 XJ inspected last month and the garage identified 3 codes. I reset the check engine light, took it to another garage and passed inspection. The engine light comes back on within 50 miles. Here are the codes:

705 - neutral safety switch - that shouldn't be a problem

455 - evap system leak - this isn't easy to tackle w/o the right equipment but someone mentioned it may have been caused by filling up your tank with the engine running....I am guilty of this, what is the specific fix if you did leave the engine running during fill-up?

442 - no clue - any help would be appreciated.

Other than 13 mpg it seems to be running fine.

thanks.

DC

442 is another related "evap leak" code. Could be as simple as a loose gas cap, or could be a bad hose somewhere. If the evap codes don't come back, don't worry about it.

I have an '01 w/ 55k miles. I get approx 13 miles per gallon. It seems to run ok although you can tell something just isn't right. What is the best approach to get the check engine light to stay off and get better gas mileage. From my research I will:

1. check or replace the gas cap
2. repair/replace vacuum hoses
3. replace plugs and wires
4. replace the upstream o2 sensor

Any other suggestions? Ceramic sensor or higher grade plugs and wires?

One last thing....I still don't get what the problem caused by filling your tank with the engine running. Can anyone explain?

thanks,

DC

bump

newer vehicles have sensors everywhere. your new jeep can sense a pressure difference with the cap on and off. and simply put........your not supposed to fill up with it running. the cars don't like that anymore. stupid bored over experienced engineers gotta put damn electronics in everything nowadays.

that's why i refuse to buy any cars that are OBD-II.