I learned something new the other day about my 2012 Max. I stopped for gas on a road trip and locked the car when I got out to pump the gas as I was going to go inside when I was done to get a coffee. Dammed if my gas flap wouldn't open! I even tried to help it with my gas card - no luck. Not wanting do any damage to the finish of the flap, I knew there was a Nissan dealer down the road so I took a ride down there. I pulled into the service bay and a nice guy came over to see what I needed. I explained my issue with the gas flap so he went over to check it out. As you have already figured out, it popped right open. We were both surprised at this. He theorized that maybe the cord on the gas cap was caught in the flap release. Seemed reasonable. I left and stopped down the road to get that coffee that I never got. Locked the car when I went inside (detect a common theme here?). When I came out I figured I'd try the flap again before I got too far from the dealer. Of course, it wouldn't open. Unknown to me and the guy at the dealer, when you lock the car, the gas flap locks as well. Makes sense but I had never tried putting gas in the car when the door was locked before this day. Live and learn.

 

It's common on newer cars, but it is not really a real lock with a latch for theft prevention. I believe it is some sort of magnetize locking device though and yes it is only activated when you lock your car doors.


In another case, if someone really want to steal your gas, they can easly pop that lid and siphon gas out.

 

It is a deadbolt or door lock of sorts.
How it works is similar to how a door closes properly no matter if the lock is "locked" or "unlocked".
Page 3-21 of the 2012 version owners manual describes how it works.

 

Lol wow u guys are killing me. Its just an actuator that prevents u pushing the door in to release it. All this speculation when all u have to do is look at the door while its open and lock the car and VOILA! u now know how it works. SMH.

 

haha same thing happened to me the other day. took me about 5 min to figure it out.

 

My 09 does the same thing

 

The previous owner of my car broke it because they didn't know how use it lol....

 

I know exactly how it works... I am describing how the actuator actually works even if it's in the locked position, albeit very badly.

 

Happened to me the first time I stopped to fill up after buying my '09 almost five years ago. It took me a minute or two to think my way through this and simply press the unlock on my fob. But there was that first quick thought of 'What tha . . .'

Since the long-ago years when I was tooling around in that black Studebaker back in 1949, there have been incredible changes in the automotive world. A few of those changes have leapfrogged my knowledge of cars, and when they pop up, I am sometimes baffled. This was one of those times.

 

Wow, the mysterious locking gas flap. I've had this on my last 4 cars the oldest being my 97 Maxima.

 

Lol. That was the first thing the sales guy told me. He said "Save some gas to the dealer and learn about the gas lid."

 

But this situation will only be encountered if we lock the car before pumping the gas. As my wife is virtually always in the car with me, I don't lock the car, else if she then opens her door from the inside, it sets off the alarm.

 

I did the same thing bro, numerous times. I think i even put a few little dents in my gas flap because because of me banging on it. I tried prying it with a credit card etc. Then read the book......i never thought i would have to read the manual on "how to open fuel door", but i did, and learned about this. Unfortunaley, my gas cap does not close flush anymore, but it's not that noticieable. That's my fault. lol