I saw something the other day that mentioned not topping off the gas, to leave room for expansion. Any truth to that?
Is it ok to top off gas?
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Any truth to that?
Yes. Read your owner's manual.
Any truth to that?
Yes. Read your owner's manual.
I'll admit, I am bad at topping off. Do it every time. But AFAIK the tank has a built in pressure relief valve, so I don't worry too much.
Before anyone else replies...I just was asking in a nice way, maybe I need more smilies. Within the last year seems like everyone gets snippy highbrow with replies. I'm just here to learn and enjoy the conversation.Like Throt's response. I'll be the first to admit I don't know much but that is why I'm here and I always enjoy the detailed responses...not RTFM.
Smilie Happy face.
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Yes, on anything with an evaporative emissions system especially, you don't want to "top off."
The big issue is you risk liquid fuel entering the evaporative emissions system, which is only meant to deal with vapor, not liquid. Liquid gas can damage the charcoal canister, which generally isn't cheap.
Just let the pump click off.
The big issue is you risk liquid fuel entering the evaporative emissions system, which is only meant to deal with vapor, not liquid. Liquid gas can damage the charcoal canister, which generally isn't cheap.
Just let the pump click off.
I routinely put 22 gallons in my official "17.5" gallon Accord allowing me to go from ~500 per tank to over ~630 per tank.
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Topping-off a gas tank is a bad idea since it can force gasoline through the gas tank's ventilation system and into your vapor canister reservoir. These ventilation canisters work fine with gasoline vapors, but liquids like gasoline usually makes them ineffective and can result in a CEL.
Charcoal vapor canisters are designed to collect the fumes (not liquids) from the evaporating fuel in the gas tank and hold them until the engine is started.
Charcoal vapor canisters are designed to collect the fumes (not liquids) from the evaporating fuel in the gas tank and hold them until the engine is started.
Originally Posted By: coopns
... snippy highbrow with replies. ...
That was VERY well put, and I'm not being sarcastic.
I still top off even in the Subaru. I know that fuel systems have progressed greatly, but still carry that habit from the old vehicles I used to drive where you could get another gallon or so in with that technique. Working on getting away from it.
... snippy highbrow with replies. ...
That was VERY well put, and I'm not being sarcastic.
I still top off even in the Subaru. I know that fuel systems have progressed greatly, but still carry that habit from the old vehicles I used to drive where you could get another gallon or so in with that technique. Working on getting away from it.
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Originally Posted By: 147_Grain
Charcoal vapor canisters are designed to collect the fumes (not liquids) from the evaporating fuel in the gas tank and hold them until the engine is started.
So that's why my garage smells like steaks a grillin' after I fire up the truck. I
Charcoal vapor canisters are designed to collect the fumes (not liquids) from the evaporating fuel in the gas tank and hold them until the engine is started.
So that's why my garage smells like steaks a grillin' after I fire up the truck. I
I've long been topping off my vehicles until it simply isn't possible to put any more in and have never had a problem.
This is going back to the seventies.
This is the only way I know of to accurately track fuel economy, since you otherwise get variable fill amounts.
Filling when you still have some distance to drive, as I typically do, probably helps in avoiding any problems.
This is going back to the seventies.
This is the only way I know of to accurately track fuel economy, since you otherwise get variable fill amounts.
Filling when you still have some distance to drive, as I typically do, probably helps in avoiding any problems.
As far as filling the gas tank, I let it fill until it does the auto click once. After it does that, I barely squeeze it and hold it until it clicks again. Then after that I'm done.
What I don't understand about people that just keep doing it is will that extra 50 cents worth of gas actually get you any further?
I haven't had any charcoal canister problems yet with my approach and in my mind, my method keeps it that way.
What I don't understand about people that just keep doing it is will that extra 50 cents worth of gas actually get you any further?
I haven't had any charcoal canister problems yet with my approach and in my mind, my method keeps it that way.
I know a guy who puts an extra gallon or so in after the pump shuts off. He was talking about how if you let a slow trickle go after the pump stops, it'll take another gallon or so before it shuts off again. I tried to explain to him why you shouldn't do that, but he insists that it doesn't apply him and it's fine to do (no it's not).
Topping up a couple of cents isn't going to do anything, but there's no reason to do that. I used to do that when I paid in cash so I wouldn't get a bunch of pennies back. But now that I use my credit card, I feel no need to top up on top of where it stopped.
Topping up a couple of cents isn't going to do anything, but there's no reason to do that. I used to do that when I paid in cash so I wouldn't get a bunch of pennies back. But now that I use my credit card, I feel no need to top up on top of where it stopped.
In many if not most owner's manuals of modern cars, even the latest ones, they state NOT to top off the fuel tank.
Fill the tank until the gas pump auto shut off clicks.
DO NOT CONTINUE TO FORCE FUEL INTO YOUR
TANK AFTER THE AUTOMATIC PUMP SHUTS OFF!
Continuing to fuel the tank may result in the evaporative
emissions charcoal canister which recovers vapors being soaked in liquid fuel, rendering it permanently damaged, and causing a check engine light to occur, requiring the canister to be replaced.
For the love of God why would you squeeze another gallon in only to cause expensive damage to your vehicle?
Fill the tank until the gas pump auto shut off clicks.
DO NOT CONTINUE TO FORCE FUEL INTO YOUR
TANK AFTER THE AUTOMATIC PUMP SHUTS OFF!
Continuing to fuel the tank may result in the evaporative
emissions charcoal canister which recovers vapors being soaked in liquid fuel, rendering it permanently damaged, and causing a check engine light to occur, requiring the canister to be replaced.
For the love of God why would you squeeze another gallon in only to cause expensive damage to your vehicle?
Originally Posted By: 01rangerxl
Yes, on anything with an evaporative emissions system especially, you don't want to "top off."
The big issue is you risk liquid fuel entering the evaporative emissions system, which is only meant to deal with vapor, not liquid. Liquid gas can damage the charcoal canister, which generally isn't cheap.
Just let the pump click off.
Good advice. I have not topped off for years because of that reason.
Yes, on anything with an evaporative emissions system especially, you don't want to "top off."
The big issue is you risk liquid fuel entering the evaporative emissions system, which is only meant to deal with vapor, not liquid. Liquid gas can damage the charcoal canister, which generally isn't cheap.
Just let the pump click off.
Good advice. I have not topped off for years because of that reason.
I add an extra gallon of gas for the past 35 years.
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Originally Posted By: 01rangerxl
Yes, on anything with an evaporative emissions system especially, you don't want to "top off."
The big issue is you risk liquid fuel entering the evaporative emissions system, which is only meant to deal with vapor, not liquid. Liquid gas can damage the charcoal canister, which generally isn't cheap.
Just let the pump click off.
Bingo. If you so desperately want to squeeze in an extra gallon, better start setting aside money for a new EVAP canister.
Yes, on anything with an evaporative emissions system especially, you don't want to "top off."
The big issue is you risk liquid fuel entering the evaporative emissions system, which is only meant to deal with vapor, not liquid. Liquid gas can damage the charcoal canister, which generally isn't cheap.
Just let the pump click off.
Bingo. If you so desperately want to squeeze in an extra gallon, better start setting aside money for a new EVAP canister.
If you bounce and jiggle some cars' rear ends, which removes trapped air from the tank, you can get a lot more gas in the tank. This is my MO when I want maximize range. Out of safety concerns I stop short of flooding the filler tube though.
Originally Posted By: antiqueshell
In many if not most owner's manuals of modern cars, even the latest ones, they state NOT to top off the fuel tank.
Fill the tank until the gas pump auto shut off clicks.
DO NOT CONTINUE TO FORCE FUEL INTO YOUR
TANK AFTER THE AUTOMATIC PUMP SHUTS OFF!
Continuing to fuel the tank may result in the evaporative
emissions charcoal canister which recovers vapors being soaked in liquid fuel, rendering it permanently damaged, and causing a check engine light to occur, requiring the canister to be replaced.
For the love of God why would you squeeze another gallon in only to cause expensive damage to your vehicle?
By the same logic we should not alter tire psi nor use after market non-oem parts. Looks like many here get away with it.
On my Jetta I always fill to the brim. My gassers tho I go to the first click and call it good.
In many if not most owner's manuals of modern cars, even the latest ones, they state NOT to top off the fuel tank.
Fill the tank until the gas pump auto shut off clicks.
DO NOT CONTINUE TO FORCE FUEL INTO YOUR
TANK AFTER THE AUTOMATIC PUMP SHUTS OFF!
Continuing to fuel the tank may result in the evaporative
emissions charcoal canister which recovers vapors being soaked in liquid fuel, rendering it permanently damaged, and causing a check engine light to occur, requiring the canister to be replaced.
For the love of God why would you squeeze another gallon in only to cause expensive damage to your vehicle?
By the same logic we should not alter tire psi nor use after market non-oem parts. Looks like many here get away with it.
On my Jetta I always fill to the brim. My gassers tho I go to the first click and call it good.
Because as I noted above, this causes no damage at all to any vehicle, or at least it hasn't to the dozen or so we've driven for the last million or so miles.
This sounds like another one of those commonplace myths, and yeah, I can read the OM as well as anyone else.
This sounds like another one of those commonplace myths, and yeah, I can read the OM as well as anyone else.
I just put $40 or $50 in at a time and call it good. Less time wasted sitting at a gas and having to listen to everybody's [censored] music blaring.
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