Throttle Response After Fillup
 

Hey guys, I've been noticing this on my cars when I fill up the tank - the throttle response immediately improves. It happens on both my CSX and the Odyssey, and it's got me scratching my head. So, I stop at the gas station, fill the car up to full, and it's as if the car is happy that it got fed.

Is this due to calibration of the ECU, or placebo effect. Anyone notice this?

If anything it should be less responsive cuz of the extra weight from a full tank of gas. =P

My girlfriend and I had the same discussion a few days ago...she claims that her car is slightly faster after filling the car up to full...I told her it should be slower due to the extra weight.

it feels faster because your wallet is lighter and your ass is now more directly connected to the seat. adding horse powers to the butt dyno

^ lol

technically the car should be slower cuz of the additional weight

its all in the mind

maybe ur letting ur tank go too empty, causing lack of fuel for the pump to be pushing.

highly unlikely, more likely its just u mentally feel its got more power.

I always thought I noticed that too, but it defies all logic.. The car should be noticeably slower after filling up, not faster. But it always seems faster. Weird.

Thats weird, I always feel slower after I fill up

seems faster in any cars ive driven

I usually fill around half-tank. And yes, I logically deduced that weight = slower car.

It's mainly in the throttle response... just seems like that the car has more pep.

Mental issues, perhaps... :cry:

mine seems heavier, and but same response

my logic to it was the weight distribution became more even

ur car now pitches more during acceleration because more mass is in the back. more g is felt from the pitching. simple as that. p-cars should be opposite

I've had the same feeling too.

my knowledge is all speculation and theory,
im assuming that the pathway hole from a gas tank to engine is located at the bottom of a V shaped gas tank, allowing gravity to get gasoline to the engine,
So,

to explain let the gas tank = a syringe pointing down so the hole/needle is at bottom.
Let the FORCE of a hand that pushes the syringe = gasoline.
So more Gasoline the tank has = more force on the syringe = faster travel of gasoline to gastank.

4.40am, half drunk, just a theory lol especially since i just filled up gas on my way home and also felt that the car is responsive.

also another theory i had is that
before going to the gas station, obviously we are near empty, so we are driving very economically and not flooring it,
but after we fill up, we lose the fear of running out of gas and drive as hard as we want.

You have a fuel pump, I think the flow rates would be the same regardless of a full tank or a half tank.

Hahaha... I concur.

More gas means gravity pushes the fuel faster down the tube into your engine = MORE POWAAAAAAAHAHHH! It's like a gravity-powered turbo, but for gas instead of air.

If you strapped a giant gas tank suspended 5 feet above your car, it would be like strapping a twin turbo with dual shot of NAWWWWS into your engine.

Wait, you drove half drunk?...

lol more gas wont "push" anything.

the fuel pump pushes the gas, and it will put the same volume of gas no matter how much gas u have in ur tank

this thread now has been KO'd

end thread^

this information is absolutely correct no matter what any one says! :thumbsup:

Fresh gas is colder than the re-circulated crap in your tank... so your fuel pump (which is in the tank, and cooled by fuel) runs cooler... so it runs better after you fill it up.

;)

I believe gas stations regulate the gas temperature to about 15 degrees celsius. So, if what you are saying is correct. I would get a monster acceleration when i go to work in the morning in the winter since its usually less than 15 outside?