Gas cap check engine light - what am I doing wrong?

So I started up my truck yesterday and suddenly got the check engine and trac off lights. I took it to the dealership and the first thing they asked was if I filled up gas recently since it could be the gas cap. I said no, but took a peak anyway incase it got loose somehow. To my surprise the gas cap was GONE. Some dipshit stole it. Why? Who knows, but I got a new one while I was there.

Anyway, I looked it up online and here, and everyone says it should go away after a few cycles and to let the truck sit for a white. I've done both, including running errands yesterday, but the lights aren't going away. Is there something I'm doing wrong, before I pick up a code scanner from walmart or take it back to the dealership?

Thanks

 

Check again to make sure wasn’t stolen again lol
you can disconnect battery & reconnect, will clear some codes

 

Disconnect the negative terminal for a couple minutes.

Or a parts store should have a scanner they'll use to read codes and clear for you.

Or there could be codes that need attention.

 

About how many miles did you drive after replacing the cap? Usually have to drive about 50 miles before the codes will clear.

As mentioned you can try disconnecting the battery to clear codes.

 

like maybe 20 miles, so not 50.

 

It takes a few days for the pcm to run another self test and see the leak go away. Certain criteria need to be met before it will even run a leak test like fuel level in tank, etc

 

Get out there and lay that mother down

 

Did you piss off someone from work?

 

Thanks for the gas cap, mine was beat so I just seen another taco, yours I guess, and popped it off and on to mine.

Kidding. That’s sucks lol!

 

Thanks for the help guys. So does disconnecting the battery actually help with this?

 

Just drive it like you stole it for a few days. Driving with a check engine light never killed anyone.

 

UPDATE: disconnecting the battery worked! Thanks everyone!

 

If you are thinking about a locking gas cap, I have the one on the left in post #61. Never had a CEL light in 8 years.

https://www.tacomaworld.com/threads/locking-gas-cap.750710/page-4

 

nice! Dooley noted, thanks for the follow up!

 

I installed a new locking gas cap supposedly correct for my 2023... and got the check light.
I put the stock cap back in place, and drove for a week... ECM did not clear the check code.
My friends at the local shop read the codes, saw it was emission related, and cleared the code with the stock cap in place.
No more check lights.