So the other week my "check gas cap" light came on. I went and readjusted the cap, came back in the car, started and it went away. Then during the next start up a day later, the check engine light came on. I freaked, called the dealer, took it in. They hooked it up and it was just the gas cap. They cleared the warning light and all was good for a week. Then the other day, the check engine light came on again, also saw a "service required" warning come up. I already had my annual service-inspection january 2016. I have been fiddling with the gas cap here and there, starting the car, driving it like usual for the past 2 days and the check engine light is still there.

Talking to the service guy and and other car guys, seems like the light may take awhile to finally go off, but my problem was how come its doing it so frequently. I feel like even if the light goes off, it'll only be a matter of days before it comes back on. I'll give it another week. Then I'll call the dealer. Is it something they can just replace easily? How common is this? Just frustrating because the car has been great otherwise. Thanks!

 

First I've heard of this issue.

 

You've got the cap tight before you start it, correct? If the gas cap has a poor seal, it will intermittently fail with a DTC (Diag trouble code). Once the dealer clears it with the laptop, it should not return. If the same code does comes back, than the underlying issue hasn't been addressed. If it's not the cap, there could also be a small leak elsewhere in the system. It's not too great of a cause for concern but certainly something to have addressed.

Hope that helps,

Ryan

 

Thanks, yes it's tight before start for sure. All of a sudden it's an issue and I'm not sure why. I haven't changed anything with the way I pump my fuel or screw the cap back on. I'll give it some more time and then we'll see.

 

Is there actually a light that says this or do you mean the check engine light?

 

Yes there was actually a warning in the center thingy where it sometimes flashes service required when it becomes due. I was surprised it had a warning like that but was really thankful for it too.

 

Sounds like you're getting two or three different type of warnings, possibly not to do with the gas cap. Have the actual codes read and post here.

 

Had the gas cap light problem 5 times over 9 months on a 2009 XF.

The fix was replacing an air pump in the gas tank and renewing the charcoal filter

 

Thanks, this is very valuable feedback. I'll be sure to bring it up to the service guy. As of now, the check engine light is still on!! Very annoying

 

Dealer started a case with Jag after I told Jag directly that I was going to start a buyback since the would not pass upcoming NC inspection. That is what got the problem off center. Haope you don't have to go that far.

 

When the light comes on, is the gas cap looser than it was? The reason that I ask is that my S2000 is having a similar issue. I tighten the gas cap after filling, but the check engine light will usually come on before I fill again. Every time it's because the gas cap has loosened itself. Obviously the most obvious solution for me is to replace the gas cap and see if the problem goes away. If your gas cap is loosening, I'd suggest the same. Heck, even if your gas cap is not loosening, I'd suggest the same (though it would be less likely to fix the issue).

 

I had a CEL after winter storage 2 years ago, and got a new vapor recovery valve (something like that) which fixed it.

 

I'd almost bet that this is the cause. It sets the same fault code as a loose gas cap.

 

welp here's the verdict. They replaced the gas cap and now just crossing fingers. I attached the service summary here in case anyone was interested or helps anyone in the future with a similar problem. Hopefully this ends the issue....but for some reason I'm not convinced quite yet.

 

I'm 99% certain was the right fix. While we may not have seen this particular fault on F-Types yet, it used to be very common on all makes and models.

This may no longer be true, but it was widely published at one point that the #1 cause of check engine lights (CELs) was gas caps not on tight or faulty.

 

spoke too soon. check engine light came on the day after i got it back. i'll be taking it back to the dealer and he said they're gonna have to start taking things apart. son of a bitch!

 

so got the car back and here's the fix, they said that some tubing was cracked and they had to replace some parts:

 

As predicted above.