Gassing Up Reply #1 – December 11, 2011, 09:50:52 PM i always shut mine off.. some cars you HAVE to shut off to fill up, or else you get that fancy CEL popping up on you.. example, pontiac trans-sport mini vans.. if you fill up with the motor running, you get a 'gas cap' code or some stupid BS.. i had to clear this code NUMEROUS times on my buddy's mom's old van, because she was too lazy to turn the key back when getting gas.. but i've always shut mine off, it's just a habit.. especially since 90% of the time, i get gas at wawa and run in to get cigarettes.. some gas 'attendants' won't even pump your gas if you don't shut the motor down Quote Selected
Gassing Up Reply #3 – December 11, 2011, 10:03:05 PM how so? i don't see the pump warming the fuel around it THAT much to really make that sort of impact.. now if it's running and there's a decent temp difference, i could see it being a problem because the 'cold' gas will possibly reach the pump before it has a chance to mix with the 'warm' fuel.. but when you fill up with the motor/pump off, it gives the gas a chance to mix..i never let mine go below 1/4 tank unless i can help it either.. mostly for the reason of 'just incase' there isn't an open gas station between point A and B Quote Selected
Gassing Up Reply #4 – December 11, 2011, 11:03:35 PM OBDII cars will throw a EVAP code if you leave them on while fueling. I never thought about pump shock. Most fuel pump failures are due to clogged fuel filters. I never fill up at a place where they are filling the tanks. When they fill their tanks it stirs up the contaminants at the bottom and you could be pumping that crud right into your tank. Quote Selected
Gassing Up Reply #5 – December 11, 2011, 11:25:40 PM Quote from: TOM Renzo;375265 Does anyone do this No. Quote Selected
Gassing Up Reply #6 – December 11, 2011, 11:32:47 PM ~Shakes head and exits thread~:punchballs: Quote Selected
Gassing Up Reply #7 – December 12, 2011, 12:24:31 AM Quote from: shame302;375281~Shakes head and exits thread~:punchballs: Quote Selected
Gassing Up Reply #8 – December 12, 2011, 01:06:28 AM Quote from: TOM Renzo;375270Yes i know but we learned in TECH school that the cold fuel shocks the hot pump if the car is not running. This is one of those questions that can be very controversial. The instructor claims it is definately something that protects the pump. Hot pump cold gas!!!!Ain't the pump immersed in the fuel in the first place....also, a tank of fuel under a car will not normally become as warm as the ambient air, even on a hot summer day....unless it's in direct sunlight or close to a source of heat. Quote Selected
Gassing Up Reply #9 – December 12, 2011, 05:04:10 AM The pump is cooled by the gas. That's why people that run their cars on empty a lot go through more fuel pumps Any time something hot is suddenly cooled, its not good for expansion. My work trucks we used to fill all the time while running. A lot of them ran 24/7 as manlift trucks that required the engine to be running for operation. Honestly, there were some days where I was pumping gas for 2-3 hours a day in running trucks. Not going to saying anything about smoking through, other then I smoked quite a bit while I was outside...I doubt the "cold" fuel would be much of an issue. Its warmed underground then it is in your gas tank in the middle of winter. At least down here anyways. Quote Selected
Gassing Up Reply #11 – December 12, 2011, 06:28:29 AM Quote from: TOM Renzo;375300..........that underground storage tanks keep the fuel fairly cold..... From my experience......yes!!! Filling a motorcycle gas tank on a hot summer then jumping on it is like putting an air conditioner in your crotch........aaahhhhhhh! Quote Selected
Gassing Up Reply #12 – December 12, 2011, 06:32:23 AM it may just be a GM thing, than.. GM's are known for destroying fuel pumps, just ask my sonoma fuel pumps always seem to be GM's big problem, along with sucky wiring Quote Selected
Gassing Up Reply #13 – December 12, 2011, 06:34:26 AM Quote from: Dan B.;375301From my experience......yes!!! Filling a motorcycle gas tank on a hot summer then jumping on it is like putting an air conditioner in your crotch........aaahhhhhhh! :rollin: :giggle: :headbang: :laughing: Quote Selected
Gassing Up Reply #14 – December 12, 2011, 11:24:27 AM I always thought running out or almost out of gas causes pump to overheat because it is designed to pump liquid and not air. Not to mention sediment in bottom of tank. Quote Selected