Gas pump always stops around 11 or 12 gallons
03-10-2010 | 04:45 PM
#34
Race Director
Joined: Sep 2006
Posts: 19,034
Likes: 255
From: Centerton, AR
It's touch and go for me. My issue is the same as the thread's author (adg). It's not that it's filled up full and the tank reads 3/4 like Pac's. So let's not get that confused. It should almost be a separate post.
I do better with the basic nozzles with no fancy gas fume breather contraption at the end of the nozzle. The kind where you push in so the mouth of the contraption can cover the gas tube on car. The straight nozzle style typically fill up till full.
It's an annoyance that just shouldn't be there in the first place (go Porsche). I don't buy the whole fill up at 1/4 else claim. The manual says nothing about this.
I'll check the fuse.
I do better with the basic nozzles with no fancy gas fume breather contraption at the end of the nozzle. The kind where you push in so the mouth of the contraption can cover the gas tube on car. The straight nozzle style typically fill up till full.
It's an annoyance that just shouldn't be there in the first place (go Porsche). I don't buy the whole fill up at 1/4 else claim. The manual says nothing about this.
I'll check the fuse.
Running gas tank level real low with submerged fuel pumps has been a problem for as long as fuel pumps moved from outside the tank to inside the tank.
Fuel systems that are on demand -- the in-tank pump only runs when fuel is required vs. full-time systems in which the pump runs constantly with fuel being routed back to tank by a fuel return line -- are less prone to being affected by running the tank low cause the fuel pump doesn't run as often and the fuel tank contents are not heated by the fuel returned which generally picks up heat while out of the tank.
Sincerely,
Macster.
03-22-2010 | 01:43 AM
#35
Thread Starter
Instructor
Joined: Jun 2009
Posts: 216
Likes: 1
Filled up the car again today at a totally different gas station (I was in a different state!) and it stopped at 11.5 gallons. I turned the handle sideways and then it filled up to 15.7 gallons.
Looks like I'll just have to keep doing that when I fill up.
- Anthony
Looks like I'll just have to keep doing that when I fill up.
- Anthony
03-22-2010 | 01:57 AM
#36
Nordschleife Master
Joined: Sep 2006
Posts: 6,194
Likes: 4
From: Temecula, CA
My car too doesn't play well with most gas nozzles. The upside down technique allows it to work, but so does holding it horizontal. I noticed that some stations now have signs saying not to hold the nozzle upside down and so, to avoid being yelled at, I tried horizontal and it worked.
The attendants here couldn't care less. As long as they are personally not on fire and can have their friends hang out at the store, they're all good.
03-22-2010 | 03:26 AM
#37
Drifting
Joined: Dec 2009
Posts: 2,919
Likes: 3
From: Aiea, HI
Just how long is the neck of the filler tube? I know for me to get a full reading its topped off to the plastic flap area. Kind of a pain when I top it off a little too much and have the fuel in the pump nozzle adding more gas when extracting the nozzle.
I just take it as when its full its full and just reset the trip odometer every filling.
I just take it as when its full its full and just reset the trip odometer every filling.
03-22-2010 | 04:39 AM
#38
Rennlist Member
Joined: Nov 2006
Posts: 1,862
Likes: 2
From: Knoxville, Tn.
During my part-time days at UPS and pumping more gallons of fuel in one day than most do in a year, gave me more insight on this phenomena than I care to mention. It's sort of a double edged sword. The reason the nozzle cuts off is simply due to one reason: The sensor/overfill-indicator at the end of the nozzle head was tripped, thus it shut off to prevent a spillage. How this sensor is tripped is the double edge sword.
Apparently our tank filler-tubes are designed such that they create froth/splash and trigger the sensor. The open tank design on the tractors were never an issue unless you literally stuck the nozzle end into the fuel, then it would shut off. Since none of our tanks are spilling onto the ground, they are obviously not "full" and being tripped by the back splash or froth. Either its a tank filler tube design flaw or a nozzle design flaw. Since most nozzles are practically the same, I say its our own vehicles causing the problem. Although, it could be that some companies set/buy their sensors a little too sensitive to prevent spillage.
Apparently our tank filler-tubes are designed such that they create froth/splash and trigger the sensor. The open tank design on the tractors were never an issue unless you literally stuck the nozzle end into the fuel, then it would shut off. Since none of our tanks are spilling onto the ground, they are obviously not "full" and being tripped by the back splash or froth. Either its a tank filler tube design flaw or a nozzle design flaw. Since most nozzles are practically the same, I say its our own vehicles causing the problem. Although, it could be that some companies set/buy their sensors a little too sensitive to prevent spillage.
03-22-2010 | 01:08 PM
#39
Porsche Nut
Rennlist Member
Rennlist Member
Joined: Jul 2003
Posts: 2,591
Likes: 147
From: CA
During my part-time days at UPS and pumping more gallons of fuel in one day than most do in a year, gave me more insight on this phenomena than I care to mention. It's sort of a double edged sword. The reason the nozzle cuts off is simply due to one reason: The sensor/overfill-indicator at the end of the nozzle head was tripped, thus it shut off to prevent a spillage. How this sensor is tripped is the double edge sword.
Apparently our tank filler-tubes are designed such that they create froth/splash and trigger the sensor. The open tank design on the tractors were never an issue unless you literally stuck the nozzle end into the fuel, then it would shut off. Since none of our tanks are spilling onto the ground, they are obviously not "full" and being tripped by the back splash or froth. Either its a tank filler tube design flaw or a nozzle design flaw. Since most nozzles are practically the same, I say its our own vehicles causing the problem. Although, it could be that some companies set/buy their sensors a little too sensitive to prevent spillage.
Apparently our tank filler-tubes are designed such that they create froth/splash and trigger the sensor. The open tank design on the tractors were never an issue unless you literally stuck the nozzle end into the fuel, then it would shut off. Since none of our tanks are spilling onto the ground, they are obviously not "full" and being tripped by the back splash or froth. Either its a tank filler tube design flaw or a nozzle design flaw. Since most nozzles are practically the same, I say its our own vehicles causing the problem. Although, it could be that some companies set/buy their sensors a little too sensitive to prevent spillage.
03-22-2010 | 07:37 PM
#40
Burning Brakes
Joined: Apr 2007
Posts: 870
Likes: 0
From: MA, the cradle of random driving
The issue with letting the gas level get real low is the fuel pump is immersed in the fuel and is cooled by the fuel. A real low fuel level means there is little fuel left to absorb the heat from the pump. The pump runs hotter.
A few instances is not sufficient to cause any problems but consistently running around with a low fuel level can over time degrade the fuel pump.
Next with a tank with low fuel there is more sloshing. If there are any contaminants in the fuel -- water mainly -- this agitates the water off of the bottom of the tank where it normall resides and mixes it in the fuel. If this fuel with water gets ingested by the fuel pump it can block the fuel filter (had a truck engine stop like a switch was thrown once when I went around a sharp corner with a low fuel tank and upon inspection found a few drops of water in the inline fuel filter which acted to completely block fuel flow until I removed filter and blew out the water). If it makes it past the fuel filter the water can result in damage to the the injectors and then of course trigger a CEL from a misfire though this will be shortlived.
I would hope the newer Porsches with direct injection systems have fitted a real good water trap to prevent any water from making it past the the 1st fuel pump into the high pressure fuel pump. If not or if it is being overwhelmed and people are driving these cars on a real low fuel tank this might account for some of the fuel pump failures these cars are experiencing. I remember from my time with my diesel powered car high pressure fuel pumps -- be they pumping diesel fuel or gas -- do not like water at all. And the fuel pump on the diesel was a very expensive item. The fuel filter -- just before the pump -- was huge and had a big water trap too. And when I drained it once in a while I always got a few drops of water out of it. So the water does make it up as far as the engine compartment.
When automakers went with in-tank fuel pumps I stopped running gas tank real low except on rare occasions. I generally fill the gas tank when level showing 1/4 tank though I do once in a great while continue to drive to the point the low fuel light comes on.
Most fuel -- just recently too -- I ever put into my Boxster's 16.9 gallon fuel tank was 15.23 gallons. Generally the fill up ranges from 10 gallons to 12 gallons sometimes getting into the 13 gallon figure.
I know -- from my Auto-Xing days -- everyone likes to run low fuel level for the weight savings. Gas weights approx. 7.5 pounds per gallon and a few more gallons of gas is not going to cost you a trophy and might save you some trouble later down the road.
Sincerely,
Macster.
A few instances is not sufficient to cause any problems but consistently running around with a low fuel level can over time degrade the fuel pump.
Next with a tank with low fuel there is more sloshing. If there are any contaminants in the fuel -- water mainly -- this agitates the water off of the bottom of the tank where it normall resides and mixes it in the fuel. If this fuel with water gets ingested by the fuel pump it can block the fuel filter (had a truck engine stop like a switch was thrown once when I went around a sharp corner with a low fuel tank and upon inspection found a few drops of water in the inline fuel filter which acted to completely block fuel flow until I removed filter and blew out the water). If it makes it past the fuel filter the water can result in damage to the the injectors and then of course trigger a CEL from a misfire though this will be shortlived.
I would hope the newer Porsches with direct injection systems have fitted a real good water trap to prevent any water from making it past the the 1st fuel pump into the high pressure fuel pump. If not or if it is being overwhelmed and people are driving these cars on a real low fuel tank this might account for some of the fuel pump failures these cars are experiencing. I remember from my time with my diesel powered car high pressure fuel pumps -- be they pumping diesel fuel or gas -- do not like water at all. And the fuel pump on the diesel was a very expensive item. The fuel filter -- just before the pump -- was huge and had a big water trap too. And when I drained it once in a while I always got a few drops of water out of it. So the water does make it up as far as the engine compartment.
When automakers went with in-tank fuel pumps I stopped running gas tank real low except on rare occasions. I generally fill the gas tank when level showing 1/4 tank though I do once in a great while continue to drive to the point the low fuel light comes on.
Most fuel -- just recently too -- I ever put into my Boxster's 16.9 gallon fuel tank was 15.23 gallons. Generally the fill up ranges from 10 gallons to 12 gallons sometimes getting into the 13 gallon figure.
I know -- from my Auto-Xing days -- everyone likes to run low fuel level for the weight savings. Gas weights approx. 7.5 pounds per gallon and a few more gallons of gas is not going to cost you a trophy and might save you some trouble later down the road.
Sincerely,
Macster.
Does the water damage injectors over time continuously, or will one hard hit do damage itself?
03-22-2010 | 09:19 PM
#41
Race Director
Joined: Sep 2006
Posts: 19,034
Likes: 255
From: Centerton, AR
When I owned a VW TDi (turbo diesel engine with direct injection) the general feeling was to run a fuel additive that well improved the fuel. I tried it and noticed no difference and since I always bought diesel fuel at a busy stations I felt I was getting the best fuel and no addtive needed.
But once when I was tipping a bottle just before filling fuel tank I looked in the bottle to see how much was left and spotted a pea sized globule of some nasty rusty water. Probably the fuel filter trap would catch/trap the water and if any did make it to filter element the filter would remove the particulate matter, but some owners advised as an added step during fuel filter changes to dump a bottle of this stuff into the fuel filter housing so when you first started the engine the fuel system from the filter down through the pump to the injectors would get a nice dose of fuel system additive/cleaner. Trouble is this could put that globule of water right into the most critical water/dirt sensitive portion of the fuel system.
With gasoline DFI and the much higher fuel pressures and multiple shots of fuel the injectors might be damaged if a large slug of water passed through one.
When I have a VW TDi with a diesel engine the concern was not only for the injectors but the fuel pump. The fuel pump on a diesel engine is a work of art and expensive as H*ll.
For gasoline DFI engines I do not know how sensitive, or even if they are sensitive at all, the high pressure fuel pump is to water.
My belief is if it not too much trouble to avoid finding out, it is best to avoid finding out. And for me it is not too much trouble to avoid running the fuel level in the fuel tank down way low. And I don't auto-x my car but if I did I'd run a 1/2 or more fuel tank and suffer the penalty of the added weight.
Sincerely,
Macster.
08-10-2010 | 02:30 PM
#42
Burning Brakes
Joined: Nov 2009
Posts: 984
Likes: 3
From: Cleveland, OH
Mine is at the dealer for this situation of not taking in any fuel. I tried 3 pumps at 2 different stations this morning and it just kept spitting back out. Luckily I was very close to the dealer. We'll see if the CPO covers it.
08-10-2010 | 06:22 PM
#43
Drifting
Joined: Dec 2009
Posts: 2,919
Likes: 3
From: Aiea, HI
Oh yah, my gauge is still screwed and doesn't register full at kick off. There is a good reason to not keep jamming the tank full which is a CEL light from the activated charcoal filter for over flow being full which does a shut off valve yada yada. So just semi double tap at fill up time.
08-12-2010 | 02:01 AM
#44
Instructor
Joined: Feb 2010
Posts: 206
Likes: 0
From: los angeles, ca
Watch out. I tried filling mine too much and then started watching an accident that ws going on between a mazarati and a civic....gas started poring out all over my brand new shoes. I ruined my shoes and got high on the way back to work.
