Ok this happens when I pull up to the pump, and have less than a 1/4 tank of gas. I do the normal routine, leave the car running, and pump on any speed, low, medium, fast... The car surges... You can here it, and look at the revs, sure enough, they surge between +-300 RPM's. I have yet to check my fuel cell to see if there is in fact a Walbro, or TRE. My hunch, is that there is infact one in there, and the pressure causes air to get in the fuel line, wich due to a faster pump, causes that wild idle surge when fueling...? I do not here a fuel pump that would power an F16(walbro) vs. the quiter stealthy, (never heard by my ears atleast) TRE. I also get 150 - 180 to the tank. DOes a faster fuel pump = lower mileage, if car is not tuned for it?

Any Ideas?

Thanks in advance.

 

bump...

 

ummm...

an open gas cap while the car is running may cause some problems. there is no need to leave the vehicle running while refueling.

 

shut the car off even with a stock fuel pump the evo will do it

 

Exactly....The fuel system is pressurized. Why would you fill your car up with gas while it's still running? Aren't there signs around that say turn off engine or something?

 

A lot off cars will even give you a CEL if it runs with the gas cap off at all, it's a part of the evap system. http://www.autoshop101.com/forms/Hybrid13.pdf

TURN IT OFF IT"S THE LAW

 

x2, I remember pulling up to a pump when it was below zero here one night. I didn't wanna cut my car off . I got the cel for the evap system. Its normal... but like the others have stated just turn the car off.

 

ummm....No it is not!
Besides there was a mith busters about all the things that cause a gas station to go boom...
Cell phones, fake
Car running, Fake

THe only thing that can set off the pump is open flame, or you getting in and out of your car, and causing static shock.

Either way, what does it matter my fueling style.

And no, not all fuel pumps, on stock vehicles, do this.
Half of you with presurization are on to something, others who are just chiming in to say something...lol...whatever.

Most gas tanks are designed with a vent. Which means weather the car is on or off, the vent on the nozzle should allow for the buildup gasses caused by the rush of gas, to exit the tank...

However, it sounds as though the buildup air bubles or gasses are being forced into the fuel line. I am aware of this happening with oversized or over pressure fuel pumps, but not with stock ones.

 

turn your car off before you freak someone out at the gas station pumping next to you!!

 

why dont you TRY the suggestions posted... you were looking for help and shooting down peoples ideas, because you dont believe them??? odd...


Answering your post:

Untuned fuel pumps = doo doo gas mileage

I also agree with the analysis that the bubbles may be creating the surging... also really consider that the EVOs fuel is a pressurized system...

 

I leave my car running all the time. No biggie. Mine usually idles like it has 272s opr something. The fuel pressure comes from the pump pressurizing the fuel system, not the tank being capped and pressurized (which is slowly vented off anyway). The only conclusion I could come to was the fuel from the hose was shooting down and agitating the fuel already in the tank, causing air bubbles, which would cause a slight drop in fuel pressure, maybe?

 

Deal with the surging if you leave the car running while refueling.

Shut the car off while refueling and no surging.

Pretty simple if you ask me. Or you can read your owners manual and avoid this useless thread altogether.

 

It may not be the law in Utah but then again you can marry your sister there and there hasn't been a vented gas cap used on a new car in over 20 years. Check you facts

 

I was not trying to insult anyone. Some of the replys just don't sound logical is all. Thanks again for your replys.