I have a problem that happens every time I fill up my tank completely. The check engine light comes on, and when tested, its the emissions light, something to do with emissions? The mechanic said the fuel sometimes spills into the systme and sets of the light, he reset it, but happens often, and it will go out after several days, any ideas? if I fill the tank close to full, it never happens

 

Try replacing the gas cap. It might not fix it, but a good place to start for only 12 bucks.

 

..probably just a loose cap or the seal is bad on the cap. No need to worry. Once you replace gas cap or tighten the loose cap the CEL light will reset itself eventually (go out).

The CEL is related to emissions control. You can get a CEL not only for just a bad seal on cap but leaving your gas cap loose, same thing for the oil cap and coolant cap. If those are all OK then the next step is to have the codes read out to see what's being reported. Your car computer reads many engine parameters and will give you the CEL warning.

You might consider getting a OBD II reader.
Having a OBD II reader to check the codes is handy to have, plus reseting the light (off) once you read the codes. If CEL comes back on I check again for other possibilities.

If your CEL is still on......and you don't have a OBD II.
Any decent independent shop, dealer or (click here) AutoZone store locator can check the codes (free) for you. If you know someone that has a OBDII reader you might also be able to get the code and figure out what's wrong yourself. Reading the code should then point you in the right direction to solve the issue. The problem is though, that the codes are not very clear and it may take some research to really pin point the actual problem.
Then I would ask for additional help with the folks at (click here) Renntech Technical Forum
(click here)
Boxster Check Engine Light Codes
(click here)
Renntech Porsche OBD-II P-code-Code Menu


You can drive with the CEL on but not flashing. If the light is flashing you should not run the car (it will damage the catalytic converters).

Good luck

BTW, here is a pic of the OBD II Scanners that
plugs right into the standard OBD II port on the Boxster under dashboard on driver side.

Actron® Pocket OBD II Code Scanner
Compact and easy to use. Diagnose problems quickly.
[align=center] [/align]

 

Yup, sounds like a bad cap to me.

 

I will try a new cap tomorrow. thanks