Re: More info :p

1999 Boxster with 127k miles.

This issue started a couple of years ago. I'd fill up the car with gas and within 10 miles my CEL goes on. P0446 code was the reading. Sometimes it would go off after the next fill up, sometimes I could make it go off by just re-seating the gas cap. So, what did I do? Bought a new gas cap. No issues at all this summer, until about a week ago. Filled up with gas and P0446 comes up within a few miles.

Anyone experience this before and have some advice? I guess I could pull the front passenger plastic wheel liner and purge some lines but I'm open to other thoughts. Thank you.

Greg
1999 Boxster

Grant

gee-lenahan-at-gee-mail-dot-com

I'll check that.

Greg
1999 Boxster

The code for the gas cap being loose is P0450 "Tank pressure sensor - Below Limit"

See here for diagnostic procedure for your code:
[www.renntech.org]

Thanks. I saw that post and was going to follow. While there is a separate code for the gas cap, I can't ignore the fact that the CEL goes on after I fill up my tank.

Greg
1999 Boxster

When you put the gas filler nozzle into the car, it pushes a flap to the side, which opens a valve that reroutes vapors through a charcoal canister. It's that system that is giving the code, not the cap itself.

That was the missing piece of information that I needed to help figure this out. I'll check my line and canister. Is there a way to test the canister?

Greg
1999 Boxster

You have to remove the wheel well liner and it's right there, connected to the fuel filler.

This video shows a good picture of it.

[www.youtube.com]

Thanks!