No CEL or similar for no fuel cap?? (1 Viewer)

[ToyotaTrk]

Can’t remember ever doing this before - lucky me or not, maybe senility setting in. On a road trip and stopped to fill up then off back down the Highway and heard a little bump noise. Looked in the side mirrors and say that I forgot to close the fuel door and had left the cap off too. They we kinda knocking on the side panel. I was surprised I didn’t get a CEL or similar.

Nothing like that for these trucks? In my wife’s car, Audi, she’ll get a CEL or similar on the dash....

 

[gaijin]

It takes a while, but you would have seen the light show.

 

[ToyotaTrk]

Tks. Probably only 5 min. 1 highway exit to another.

 

[sanshin]

Not sure what year you’ve got, but I have a ‘21 and didn’t tighten the cap all the way after filling up. Drove 15 miles without warning, got home and shut the car off. Next time I got in to go somewhere, the warning light came on and a message was displayed to check the fuel cap. Tightened it and restarted the car to make it go away.

 

[ToyotaTrk]

2018. Weird, maybe Signatures don’t show on iOS mobile version. I have vehicle details in my signature.... anyhow, 2018 model. Maybe it’s that I noticed it after driving a bit, pulled over before the car noticed and put the cap on while the engine was still running. I just thought I would have seen a light or something while driving off from the pump.

 

[TeCKis300]

As I understand it, the fuel system and evap canister tests occur when the vehicle is off. Some of them are 2 drive cycle faults before they illuminate a CEL.

Not sure what year you’ve got, but I have a ‘21 and didn’t tighten the cap all the way after filling up. Drove 15 miles without warning, got home and shut the car off. Next time I got in to go somewhere, the warning light came on and a message was displayed to check the fuel cap. Tightened it and restarted the car to make it go away.

This is the first I've heard of a cap specific warning. Perhaps they finally improved the warnings in the latest models years?

 

[bloc]

As I understand it, the fuel system and evap canister tests occur when the vehicle is off. Some of them are 2 drive cycle faults before they illuminate a CEL.

This exactly.

The somewhat frequent posts of people asking about a pump or motor running under the back of the truck when parked.. that is exactly what is happening.

It runs the pump to apply slight pressure or vacuum to the tank.. checking to see if it can build in the first place, and if so how quickly it goes back to ambient, indicating a leak.

This is a precision operation and therefore can’t be done while running due to it being too dynamic of an environment.. between vacuum levels provided by the engine changing, fuel level and temp changing, etc.

 

[ToyotaTrk]

Sweet. Tks. Very informative.

 

[sanshin]

2018. Weird, maybe Signatures don’t show on iOS mobile version. I have vehicle details in my signature.... anyhow, 2018 model. Maybe it’s that I noticed it after driving a bit, pulled over before the car noticed and put the cap on while the engine was still running. I just thought I would have seen a light or something while driving off from the pump.

Yep, can't see signatures when browsing mobile. Nice color combo you've got there - of course, I'm biased ; )

 

[CharlieS]

On my mobile device (iOS) signatures aren’t visible in portrait orientation, but are in landscape.