Hello everyone!
Just drove home my new to me XK8 convertible. The test drive a month ago and the 45 minute drive home were normal. Just to a friend for a ride with the top down and noticed a little later the "check gas cap" warning in the speedo and the check engine light. I pulled over to check it and could not get the filler door to open. Glad the Gent that sold it to me filled the tank. I peeled back the panel in the trunk, or boot, whatever it is and see a solenoid. I'm pretty sure I'll get the door working ok, but how about clearing the gas cap warning? Is it like most cars, and will just clear itself after awhile? Or will it need to be reset somehow? Will the car be ok to drive until I get this fixed or will it go into some sort of limp mode? And last, can this warning be something other than the gas cap?
Thanks,
Jack

 

If the only reason for the check engine light is the gas cap, then no real harm to come, however, there is no way to know if there are other issues also causing the check engine light. So, until you know what codes you have, you may want to park it (I would). Go get an obd2 reader, and check for codes, and you can clear them too. But write them down first. Come back to the thread and post the codes for further advice. Also, make sure your gas cap is on correctly. If it is your only code, it could be a fluke, or just a bad gas cap.

Obd readers are cheap. Elm327 is what you need. Amazon, ebay, etc. if you have an android phone, get a bluetooth, and you pair the elm with it, and use an app called Torque. If you have an iPhone, you need to buy a wifi, not bluetooth. You can download DashCmd to read and clear codes.

Please tell us your model year, and better, place it is your signature line, and read the stickies on the forum.

Welcome to the family.

 

The system can't really tell if your gas cap is stuck but it does read the pressures within the emission system relative to the purge valve and the possibility of the system venting to the atmosphere. What probably happened was it read a high pressure within the system and since a bad gas cap is often a cause of emissions system problems it flagged that first.


Your inability to manually open it was probably do to the tank being pumped down enough to cause a vacuum to form making it difficult for you to twist the cap off. The time you took to get to the trunk release should have allowed the pressure to equalize since the fuel pump would have been off.

Yes, and OBDII reader wo9ulod be a good investment and for under $40 could save you a lot of money down the road. For the moment I'd probably think bad purge valve in the emissions system.

 

What year car? Please update your signature so we see this information.

 

I've gotten this 4 times in 2 years, I'd reconditioned the gas cap after the first 2 then it came back, I have a purge valve in a box, I was thinking of installing it last month when I was doing maint on some other stuff, but since everything looked ok hose/connector wise and its a very rare occurrence I'm going to wait. So it's not totally a show stopper but since the car is new you will want to start keeping a laundry list of things that pop up and DATES they occur.

Ditto on the OBDII reader, (I do have to reset the CEL with above issue).
There's a sticky on OBDII DIY section I believe you may want to check out.

Good Luck and enjoy your new ride.

 

Thanks all, yes an OBD II Is on the way. I figured out the car has to be off to open the filler door. The cap seal was damp with fuel, so I cleaned it up and it was ok for a while but then the warning came on again. I also noticed a slight smell of gas with the top down
And I did update my info.
Thanks again, and thanks to whoever corrected the typo in my title box!

 

Sounds like excessive pressure so you are probably looking at the purge valve first. Fairly easy dyi and SNG has the part reasonably priced.
You remove drivers side front wheel, remove wheel well liner.

 

It would be nice to have it in your signature.
Click "User CP" on the left of the black bar at the top of the page, then in the menu at the left of the page and click "Edit Signature" under the Settings & Options heading enter your info in the box and don't forget to click the "save signature" button at the bottom when you are done.
It should show up with your next post.