Driving without fuel cap
Laughing Gas
Joined: Jun 2020
Posts: 778
Likes: 14
From: Seattle area, WA USA
Yep, probably a code, but that will correct. Maybe some fuel loss if you topped it off. You might try some duct tape if you need, but I'd avoid sticking a rag in there for the "Molotov Cocktail" look....
Senior User
Joined: Mar 2014
Posts: 443
Likes: 30
If it is a gas engine truck it may throw a code as it monitors fuel system integrity for evaporative emissions, if it is a diesel it shouldn't throw any codes, the diesel tank is not a closed system, no evap emissions requirements.
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From: Frederick, MD
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Laughing Gas
Joined: Oct 2018
Posts: 767
Likes: 78
From: NC
Left the cap off my diesel once. No codes. Thankfully had the tether on it. Found it the next day after "camping" in a truck stop (in the auto section). Got an uneasy felling someone could have tampered, added something to the fuel. No issues, so I guess I just forgot it.
Still pretty lame they couldn't have it just lock the fuel door when the truck is locked. Like it does on my other cars. It's not a new technology or anything. lol. I know it won't fix my forgetfulness, but I could at least have peace of mind the rest of the time that someone hasn't done something nefarious while the truck was unattended.
Still pretty lame they couldn't have it just lock the fuel door when the truck is locked. Like it does on my other cars. It's not a new technology or anything. lol. I know it won't fix my forgetfulness, but I could at least have peace of mind the rest of the time that someone hasn't done something nefarious while the truck was unattended.
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Fleet Mechanic
Joined: Feb 2018
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Well...yeah...I guess I assumed he had to drive an hour before he got to a place like that. If you can buy a replacement cap, go for it.
Junior User
Joined: Apr 2017
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Fleet Mechanic
Joined: Feb 2018
Posts: 1,592
Likes: 204
Diesel has a regular cap.