Gas Cap Work Itself Loose?

[mtofell]

I've found all the threads about the error code, etc. but this is just a question about the cap itself. Has anyone had one come loose on its own? I got the code this morning and when I checked, the cap was completely unscrewed and fell out when I opened the fuel door.

I'm always very diligent about screwing the cap on but am not above thinking it was "user error". But the odd thing is I'm 250 miles and +/- a week since my last fill and would think I'd have gotten the message much sooner? I guess this leads to another question - How long after the cap is loose does the code pop up? I also thought about vandalism/someone stealing gas but I checked my driveway camera and didn't find anything.

 

[Ken226]

The PCM runs the EVAP system test every time the engine has a warm up /drive awhile/ cool down cycle.

So, likely, when you saw the gas cap code, the cap got unscrewed immediately before your last use of the truck. My best guess is that it was about 3am, the night before.

I'd much more suspect a neighborhood gas thief than the cap spontaneously unscrewing itself. Considering, the clickity click torque limiter in the cap clicks at just the right torque value for the cap to function correctly. And, not unscrew itself.

Truck kept in a garage? Or in a neighborhood that has broke people (the poors) with cars?

 

[mtofell]

So, likely, when you saw the gas cap code, the cap got unscrewed immediately before your last use of the truck. My best guess is that it was about 3am, the night before.


Truck kept in a garage? Or in a neighborhood that has broke people (the poors) with cars?

Out in front of the garage, nice neighborhood on a culdesac with zero crime for the +/- 20 years we've been here. Also, I have a camera directly on that side of the truck and found nothing last night.

 

[Wild one]

Out in front of the garage, nice neighborhood on a culdesac with zero crime for the +/- 20 years we've been here. Also, I have a camera directly on that side of the truck and found nothing last night.

Could of been else where like a parking lot a day or 2 ago,and it took it a few miles to finally vibrate loose enough to cause a code. Maybe somebody started to loosen it with the thought of getting some free gas,then got scared away

 

[Ken226]

Could of been else where like a parking lot a day or 2 ago,and it took it a few miles to finally vibrate loose enough to cause a code. Maybe somebody started to loosen it with the thought of getting some free gas,then got scared away

I had 2 cousins when I was a kid, like 6 or 7 years old, decided to help dad fill up the dual tanks on his F350 dually.

It took them about 8 hours to make a couple hundred trips from the sand box over to the dually before they finally got both tanks topped off and packed down tight level with the filler neck.

That's definitely the maddest I've ever seen another human being.

Kids will definitely mess with a gas cap.

 

[Wild one]

I had 2 cousins when I was a kid, like 6 or 7 years old, decided to help dad fill up the dual tanks on his F350 dually.

It took them about 8 hours to make a couple hundred trips from the sand box over to the dually before they finally got both tanks topped off and packed down tight level with the filler neck.

That's definitely the maddest I've ever seen another human being.

Kids will definitely mess with a gas cap.

Years ago my cousin was working on his 429 Cobra Jet Cyclone,and he had the carb off ,when his son who was about 4 at the time decided to help Dad tidy up,by dropping a couple small nuts down the intake,the ports on those old 429 heads were just big enough to digest a couple small nuts,lol