thanks
Fuel Range when empty
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From: San Francisco Bay Area
MB C230K
Fuel Range when empty
I let my fuel run really low last week and noticed that the Fuel Range indicator in the MFD jumped from between "5 miles" to "70 miles". I saw that it correlated with the level of the car - the numbers change as I was heading up hill, downhill, etc. I thought this was pretty weird - surely the MB engineers would have come up with some programming to even out these types of discrepencies - after all - the car is programmed to do so many other things for you? And knowing that you have 5 miles of gas left in your tank vs. 70 miles - I would say that's critical information.
Is this normal behavior? Don't answer if you live in Ohio (too flat to notice the problem).
--Steffen
Is this normal behavior? Don't answer if you live in Ohio (too flat to notice the problem).
--Steffen
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From: Houston, TX
2002 C240 6 spd manual
There's a simple solution - go to the gas station!
The computer already calculates the range based on the average mpg times the amount of fuel sensed in the tank (which changes due to hills, hard acceleration/braking - try pouring some liquid in a glass and tilt it - similar thing going on in your tank). A baffled tank would help minimize the variation some, but at what expense is this worth it? By the time you get to 70 miles range remaining the computer has probably already turned on the idiot light saying "Reserve Fuel - Visit Refueling Station". What else do you need?
The computer already calculates the range based on the average mpg times the amount of fuel sensed in the tank (which changes due to hills, hard acceleration/braking - try pouring some liquid in a glass and tilt it - similar thing going on in your tank). A baffled tank would help minimize the variation some, but at what expense is this worth it? By the time you get to 70 miles range remaining the computer has probably already turned on the idiot light saying "Reserve Fuel - Visit Refueling Station". What else do you need?
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From: Ohio
2010 C300 4matic
Re: Fuel Range when empty
Originally posted by steffen
Is this normal behavior? Don't answer if you live in Ohio (too flat to notice the problem).
Is this normal behavior? Don't answer if you live in Ohio (too flat to notice the problem).
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I agree the variance is normal (or that I've noticed it, too). I also agree that it doesn't need to be.
If you're driving a 700 mile trip, it takes an extra fuel stop (3 total)to make the trip if you stop as soon as it falls to 3/8 full. So, I make two stops and look for the station when the car needs gas, not when it reaches 3/8 or even 1/4. In that situation, the last 1/4 tank can be interesting with hills. But, IMO, there's no reason to stop with 70 miles (better than 3.5 gallons) left in the tank.
If you're driving a 700 mile trip, it takes an extra fuel stop (3 total)to make the trip if you stop as soon as it falls to 3/8 full. So, I make two stops and look for the station when the car needs gas, not when it reaches 3/8 or even 1/4. In that situation, the last 1/4 tank can be interesting with hills. But, IMO, there's no reason to stop with 70 miles (better than 3.5 gallons) left in the tank.
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From: Dallas
C32 AMG
Not only the level of the fuel, but your mileage is changing as you go up and down hills.
Your poor car keeps trying to calculate the range, but you keep changing its little world!
BTW, I've noticed that when my C32 Low Fuel indicator lights up, I'd better find fuel IMMEDIATELY. I seem to have maybe 20 miles or so.
Our ML is not so strict, more like your 70 miles. Don't know why - they get about the same miliage.
Your poor car keeps trying to calculate the range, but you keep changing its little world!
BTW, I've noticed that when my C32 Low Fuel indicator lights up, I'd better find fuel IMMEDIATELY. I seem to have maybe 20 miles or so.
Our ML is not so strict, more like your 70 miles. Don't know why - they get about the same miliage.
Last edited by jswedberg; Jan 23, 2003 at 05:39 PM.
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From: Ohio
2010 C300 4matic
I was out driving in a G500 last week and it gets horrible gas mileage. I was watching my range in miles, but when the reserve light comes on, it says -R- miles. So that doesn't help you too much. You have to rely on the gauge, which I have seen those move around quite a bit too on some cars.
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From: Dallas
C32 AMG
Of course, a truly good boy (or girl) wouldn't allow their fuel to drop down to the reserve level, because there is always nasty crud down there at the bottom of the tank.
(BTW I am NOT a TGB!)
(BTW I am NOT a TGB!)
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From: Houston, TX
2002 C240 6 spd manual
On my last 1400+ mile trip to Florida I was getting 31 mpg for the entire trip. I figure that puts me at 2.25 gallons left in the tank, slightly more than 1/8 tank......just before the idiot light comes on.
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From: www.Traben-Trarbach.de
MPG+ ROLFCOPTER
Ok I'm in the real flatlands; the midwest north of TX. On mine I actually noticed that the gage is very accurate. Every 1/8 mark equates to 2 Gal. ***** me even tested this accuracy between 1/2 and the idiot light(1/8).
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From: Reno, NV
C240/6 Megma Red
I'm not on a flat land (reno, NV). This happen to me when I just had a car for 3 months. I'm going up and dowm the small hill. I run another 6-8 miles after the display show 0 mile on the flat Freeway.
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From: San Francisco Bay Area
MB C230K
Thanks for the replies everyone.
Re baffles, I think there would be a solution without requiring you to put baffles in the fueltank. The car should just be smart enough to know when the fuel level changes drastically that the data is an aberration. It should interpolate the readings over say, a period of 5 minutes or so. This won't help you if you're driving up hill an extended period of time. My minivan does this - it's not rocket science. ESP on the other hand is rocket science!
Regarding the idiot light - well, you know once they tell you the fuel range some idiot (like me) will think 70 miles is way too early to stop for gas. That's why they put that disclaimer in the manual.
Regarding the photos - yes I finally took some pictures today but the color didn't turn out - not enough light. I'll try again tomorrow.
--Steffen
Re baffles, I think there would be a solution without requiring you to put baffles in the fueltank. The car should just be smart enough to know when the fuel level changes drastically that the data is an aberration. It should interpolate the readings over say, a period of 5 minutes or so. This won't help you if you're driving up hill an extended period of time. My minivan does this - it's not rocket science. ESP on the other hand is rocket science!
Regarding the idiot light - well, you know once they tell you the fuel range some idiot (like me) will think 70 miles is way too early to stop for gas. That's why they put that disclaimer in the manual.
Regarding the photos - yes I finally took some pictures today but the color didn't turn out - not enough light. I'll try again tomorrow.
--Steffen
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Originally posted by jswedberg
Of course, a truly good boy (or girl) wouldn't allow their fuel to drop down to the reserve level, because there is always nasty crud down there at the bottom of the tank.
(BTW I am NOT a TGB!)
Of course, a truly good boy (or girl) wouldn't allow their fuel to drop down to the reserve level, because there is always nasty crud down there at the bottom of the tank.
(BTW I am NOT a TGB!)
Bottom line: Real Men buy gas only when the car needs it...
Last edited by MB-BOB; Jan 24, 2003 at 11:33 AM.
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From: York, PA
2003 C230K Sport Coupe, 1986 190E 2.3
I agree MB-BOB, on my old Neon I used to wait until the light started flashing at me before filling up. The light came on solid then after there was only half a gallon left it would flash at you. It is thrilling to see if you can make it or not. Like on Seinfeld when Kramer was testing out a Saab for Jerry and they drove until the thing ran out of gas just to see how far it would go.
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From: Baltimore, MD
the furtherest i have let it go was when the needle was touching the begining edge of the E indicator bar, analog is better in some cases i think. i am afraid to drive further than that without refuleing.
question: if you let the fuel get to low and the car gasps for fuel, can this damage you car?
question: if you let the fuel get to low and the car gasps for fuel, can this damage you car?
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From: Houston, TX
2002 C230 Coupe Black/Charcoal C5 C7 Auto
I agree w/ alot of ppl. where the car calc. based on your driving characteristics (i.e sitting in traffic vs cruising) there is a HUGE diff. Another thing is i do the same where i usually dont fill my car w/ more than half tank and wait till the light comes on to fill up...that way gas stay "fresh", u save some weight. Although most i've gone with is 10 mi to empty.
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Originally posted by CarlssonPower
I have an extremely dumb question: how do you set the computer to calculate the mileage left? Sorry for this dumb question.. :o
I have an extremely dumb question: how do you set the computer to calculate the mileage left? Sorry for this dumb question.. :o
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From: Houston, TX
2002 C230 Coupe Black/Charcoal C5 C7 Auto
Originally posted by CarlssonPower
I have an extremely dumb question: how do you set the computer to calculate the mileage left? Sorry for this dumb question.. :o
I have an extremely dumb question: how do you set the computer to calculate the mileage left? Sorry for this dumb question.. :o
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Cars
when reading the post and seeing that it went from 5 mile range to 70 I was thinking about my brothers '97 C230 (non-kompressor) he gets 300 miles to the tank everytime. He read in his manual that after the fuel gauge reads empty, the car has a 5 gallon reserve tank. So basically he waits a week after it first reaches empty and he's never gotten to the point where he has to get out and push. Do we have the same kind of system in ur 203z?
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2010 C300 4matic
That doesn't sound right about the 5 gallon reserve tank, especially after it hits empty. Maybe it has 5 gallons left after the light comes on, but even that seems like a lot. The 203 has a certain number of gallons after the light comes on, I forget how much. I'm sure someone else knows, or you can look in the manual. But it's not 5 gallons.
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From: Houston, TX
2002 C230 Coupe Black/Charcoal C5 C7 Auto
Originally posted by Matt230K
That doesn't sound right about the 5 gallon reserve tank, especially after it hits empty. Maybe it has 5 gallons left after the light comes on, but even that seems like a lot. The 203 has a certain number of gallons after the light comes on, I forget how much. I'm sure someone else knows, or you can look in the manual. But it's not 5 gallons.
That doesn't sound right about the 5 gallon reserve tank, especially after it hits empty. Maybe it has 5 gallons left after the light comes on, but even that seems like a lot. The 203 has a certain number of gallons after the light comes on, I forget how much. I'm sure someone else knows, or you can look in the manual. But it's not 5 gallons.
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2010 C300 4matic
Originally posted by tberry
and when the needle hits E there is no 'below E'..... E means push time baby
and when the needle hits E there is no 'below E'..... E means push time baby
