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Hello All,

I just purchased a 2011 328i sulev w/ 101k miles. When I got the car it had a little less than 1/2 tank of fuel. Once I ran it low enough to trigger a fill up at the gas station I proceed to do just that. I started filling the tank and the gas pump clicked off at around 6 gallons. I thought this was odd, so I just kept clicking the gas pump and turn the pump as I thought the pump was malfunctioning, until gas started to overflow from the car. I cleaned up and decided to get in the car and the fuel gauge only read at a 1/2 tank. I decided to move on with my business. A week later fuel light caMe on, time to fill up. Again, started to pump gas, now at a different gas station, and wouldn***8217;t you now, pump clicks of at 6-7 gallons. Go back to the car and fuel gauge reads 1/2.
What is going on? Anyone out there having or had the same issue?
 

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Are you the type to always top off your fuel more and more when it was already full? If so, you probably have fuel in your charcoal canister. You may also have a full tank but your fuel level sensor is reading wrong because it is defective. Sulev cars are known to have issues with the complete gas tank and with your miles, should be covered up to 150k miles.
 

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No I haven***8217;t had a chance to top off a full tank as this occured on the first attempted fill up since owning the vehicle.
 

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Hello All,

I just purchased a 2011 328i sulev w/ 101k miles. When I got the car it had a little less than 1/2 tank of fuel. Once I ran it low enough to trigger a fill up at the gas station I proceed to do just that. I started filling the tank and the gas pump clicked off at around 6 gallons. I thought this was odd, so I just kept clicking the gas pump and turn the pump as I thought the pump was malfunctioning, until gas started to overflow from the car. I cleaned up and decided to get in the car and the fuel gauge only read at a 1/2 tank. I decided to move on with my business. A week later fuel light caMe on, time to fill up. Again, started to pump gas, now at a different gas station, and wouldn't you now, pump clicks of at 6-7 gallons. Go back to the car and fuel gauge reads 1/2.
What is going on? Anyone out there having or had the same issue?
Service station gas pumps have a sensor in the nozzle to detect back flow of gasoline and automatically stop the pumping of gas. The sensor is activated when there is gasoline backup even when the tank is not filled. This can happen if there is some obstruction in the fill tube or if the fill tube is too narrow. But, in your case, it appears that your tank is actually full, even though your gas gauge indicates that the tank is only half full.

I believe that your car has a 16 gallon capacity and an MPG rating of 18 city / 28 highway. So, keep a pad and pencil with you in the car to keep track of your mileage. When the fuel light comes on again, calculate how much gas you have used based on miles driven. I'll lay money that you will discover that you have a malfunctioning gas level sensor in your fuel tank.
 

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Discussion Starter #6
Service station gas pumps have a sensor in the nozzle to detect back flow of gasoline and automatically stop the pumping of gas. The sensor is activated when there is gasoline backup even when the tank is not filled. This can happen if there is some obstruction in the fill tube or if the fill tube is too narrow. But, in your case, it appears that your tank is actually full, even though your gas gauge indicates that the tank is only half full.

I believe that your car has a 16 gallon capacity and an MPG rating of 18 city / 28 highway. So, keep a pad and pencil with you in the car to keep track of your mileage. When the fuel light comes on again, calculate how much gas you have used based on miles driven. I'll lay money that you will discover that you have a malfunctioning gas level sensor in your fuel tank.
After how many miles of driving and under what driving conditions?
Left the dealership with a half tank, ran it to gas light comes on, attempted to fill her, gas clicked at 6 gallons.
 

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Discussion Starter #7
Service station gas pumps have a sensor in the nozzle to detect back flow of gasoline and automatically stop the pumping of gas. The sensor is activated when there is gasoline backup even when the tank is not filled. This can happen if there is some obstruction in the fill tube or if the fill tube is too narrow. But, in your case, it appears that your tank is actually full, even though your gas gauge indicates that the tank is only half full.

I believe that your car has a 16 gallon capacity and an MPG rating of 18 city / 28 highway. So, keep a pad and pencil with you in the car to keep track of your mileage. When the fuel light comes on again, calculate how much gas you have used based on miles driven. I'll lay money that you will discover that you have a malfunctioning gas level sensor in your fuel tank.
Im not a mechanic by no means and new to the BMW world. My 328I is a SULEV and from what I have read, the gas tank is sealed. With that said, if anything malfunctions within the tank its going to require a tank replacement, true statement?

John
 

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Im not a mechanic by no means and new to the BMW world. My 328I is a SULEV and from what I have read, the gas tank is sealed. With that said, if anything malfunctions within the tank its going to require a tank replacement, true statement?

John
My understanding is that is correct. So, it is very important to test the fuel usage yourself as I suggested.
 

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Left the dealership with a half tank, ran it to gas light comes on, attempted to fill her, gas clicked at 6 gallons.
Again, you are making judgments based on the gas gauge reading. I believe that is very likely that the gas gauge is receiving incorrect fuel level information from the fuel level sensor in the tank.
Calculate your fuel level manually using the method I suggested. Fill the tank and keep track of your mileage.
 

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Left the dealership with a half tank, ran it to gas light comes on, attempted to fill her, gas clicked at 6 gallons.
Again, you are making judgments based on the gas gauge reading. I believe that is very likely that the gas gauge is receiving incorrect fuel level information from the fuel level sensor in the tank.
Calculate your fuel level manually using the method I suggested. Fill the tank and keep track of your mileage.
So just to make sure I understand this test... gas light comes on, fill the tank as much as it lets me, usually 6 gallons. I drive the vehicle and track my mileage until my fuel light comes back on. Based on an average mpg of 18 which is pretty close to what I get, if I drive 100 some miles and the light comes back on. What exactly is that telling me?
 

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What is going on? Anyone out there having or had the same issue?
Fuel nozzle automatic Venturi shut-off is triggered when liquid reaches the sensor port. Early is due to filler pipe restriction and / or faulty vent.
 

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So just to make sure I understand this test... gas light comes on, fill the tank as much as it lets me, usually 6 gallons. I drive the vehicle and track my mileage until my fuel light comes back on. Based on an average mpg of 18 which is pretty close to what I get, if I drive 100 some miles and the light comes back on. What exactly is that telling me?
Okay, based on an average mpg of 18, you should be able to drive at least 288 miles per tank full of gas.
1. Fill your tank and write down your odometer reading.
2. Your gas gauge reads only half full, which is an error.
3. You drive until the refuel light comes on.
4. Check how many miles you have driven. 100?
5. You have proven that your tank is NOT empty, it is more than half full.
6. Answer: faulty fuel level sensor in tank.

The person who sold you the car was most likely aware of the problem.
 

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You have a faulty fuel level sensor. I've seen them read incorrectly or they bind causing the gauge to stick. The sensor is on a plastic slide and over time it can groove. If your sulev, you'll be covered up to 150k miles so go take it in depending on your state. You will need to contact a center too see. . You'll most likely get a new tank. Is your engine series a n51?
 

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Discussion Starter #14
You have a faulty fuel level sensor. I've seen them read incorrectly or they bind causing the gauge to stick. The sensor is on a plastic slide and over time it can groove. If your sulev, you'll be covered up to 150k miles so go take it in depending on your state. You will need to contact a center too see. . You'll most likely get a new tank. Is your engine series a n51?
Correct, vehicle has the n51. Looks like I'm screwed on the SULEV warranty, as I'm in Pennsylvania with a 2011.
 

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Okay, based on an average mpg of 18, you should be able to drive at least 288 miles per tank full of gas.
1. Fill your tank and write down your odometer reading.
2. Your gas gauge reads only half full, which is an error.
3. You drive until the refuel light comes on.
4. Check how many miles you have driven. 100?
5. You have proven that your tank is NOT empty, it is more than half full.
6. Answer: faulty fuel level sensor in tank.

The person who sold you the car was most likely aware of the problem.
So basically your assuming when my fuel light comes on, I still potentially have 10 gallons left of fuel in the car but getting a false read on my gauge. And I would agree with that assumption as the 4 times I filled up i was only able to put 6 gallons give or take.
 

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So basically your assuming when my fuel light comes on, I still potentially have 10 gallons left of fuel in the car but getting a false read on my gauge. And I would agree with that assumption as the 4 times I filled up i was only able to put 6 gallons give or take.
Exactly, and you can prove it by the method I outlined. Or, you can prove it by ignoring the refuel light and drive 250 miles before refueling.

As BMWtechN63 noted, you may be under extended BMW warranty.
 
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