MPG ? is this right
12-03-2012, 08:09 PM
#26
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I tested my onboard computer when first got car in 2010 by comparing it to number of gallons to fill vs. miles driven. Onboard computer read about 1 MPG lower than actually getting. Of course, using measurements at pump are variable also as to when it cuts off and how full tank actually is. I used same station and pump when I did my test.
My best ever MPG was 32 at 60 with cruise, windows up and AC off on the interstate. Recent trip I averaged about 28 on interstate at 65-70+ MPH with cruise on.
Your mileage will vary!
Ethanol cuts into the fuel mileage and it is about to go to 15% fairly soon.
One problem with onboard computer is that when you reset it, it defaults to about 22 MPG, so you have to drive some distance for it to start making up for that.
I have had cruise on 60 going downhill and with foot off accelerator and reset computer, always starts at about 22, even though the car is actually getting 50-75+ MPG.
BTW, I add Techron to the fuel every 5-7,500 miles. Dealer also does it when I take it in for service. MBUSA approves of Techron as an additive.
I frequently drive within a two mile radius of home with several stop signs and it averages about 17 MPG then. Never get over 35 MPH.
My best ever MPG was 32 at 60 with cruise, windows up and AC off on the interstate. Recent trip I averaged about 28 on interstate at 65-70+ MPH with cruise on.
Your mileage will vary!
Ethanol cuts into the fuel mileage and it is about to go to 15% fairly soon.
One problem with onboard computer is that when you reset it, it defaults to about 22 MPG, so you have to drive some distance for it to start making up for that.
I have had cruise on 60 going downhill and with foot off accelerator and reset computer, always starts at about 22, even though the car is actually getting 50-75+ MPG.
BTW, I add Techron to the fuel every 5-7,500 miles. Dealer also does it when I take it in for service. MBUSA approves of Techron as an additive.
I frequently drive within a two mile radius of home with several stop signs and it averages about 17 MPG then. Never get over 35 MPH.
Your car mpg is very much the same as my 2011 E350 was.
12-03-2012, 08:44 PM
#27
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2024 AMG EQE SUV , 2021 E63S Wagon - gone, 2018 E63S Sedan - gone
Not sure what changed, but over the past couple days I have seen a significant change in fuel economy. Just today driving in to the office I was at 21ish mpg in traffic and on the way home is was at about 25mpg (very little traffic) driving normally but watching. Compare this with last week where I was getting around 19 in and 21 home in similar conditions.
Am I magically driving more efficiently, probably not but what do I know...
is the car learning something?
did something "fix" itself (I didn't get a chance to get the STP)?
Am I magically driving more efficiently, probably not but what do I know...
is the car learning something?
did something "fix" itself (I didn't get a chance to get the STP)?
12-03-2012, 11:23 PM
#28
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12-04-2012, 07:56 AM
#29
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2024 AMG EQE SUV , 2021 E63S Wagon - gone, 2018 E63S Sedan - gone
The engine takes longer to reach normal operating temp, the catalytic convertors have to be warmed up, all of which makes the transmission stay in lower gears and the engine rpms to be increased until everything settles out.
12-04-2012, 12:00 PM
#30
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2017 CLS550, 2016 HD Roadglide (120ST), 1972 Super Beetle
I've getting a very consistent 25 MPG combination (70% highway) with my 13 E350.
I'm very satisfied with it. I'm going to make a 200 mile trip on Thursday, so will check the true hwy mileage then.
I'm very satisfied with it. I'm going to make a 200 mile trip on Thursday, so will check the true hwy mileage then.
12-04-2012, 10:37 PM
#31
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This was with my previous car the 2011 E350. I always use the highest octane I can find. In some stations it is 91, others say 93. I have learned that 93 or even 91 is not what they advertice in MOST of the gas stations. You can really feel when you hit a pump where the octane really is 93.
If you fill-up with lower octane you will loose fuel mileage 10 - 15%. I rather try to get the highest octane and pay that 10 - 15% more and get more mileage and POWER from the engine.
If you fill-up with lower octane you will loose fuel mileage 10 - 15%. I rather try to get the highest octane and pay that 10 - 15% more and get more mileage and POWER from the engine.
12-10-2012, 10:34 AM
#32
Super Member
Thread Starter
Just to follow up, things are much better now. Again, I am not sure what made the difference and I am curious to know.
Last fill gave me about 20mpg mixed, 60%Cty 40%hwy. This is what I expected when I bought the car.
It is funny, but over the course of the 1 month + that I have owned the car the fuel usage improved a good 20% without really doing anything. Perhaps there is some learning going on by the car and perhaps me as well. Considering that the car was sitting on the dealers lot for a good month, only being driven by people on test drives (don't know about you, but I actually test the car on test drives and I expect others drive similarly).
Last fill gave me about 20mpg mixed, 60%Cty 40%hwy. This is what I expected when I bought the car.
It is funny, but over the course of the 1 month + that I have owned the car the fuel usage improved a good 20% without really doing anything. Perhaps there is some learning going on by the car and perhaps me as well. Considering that the car was sitting on the dealers lot for a good month, only being driven by people on test drives (don't know about you, but I actually test the car on test drives and I expect others drive similarly).
12-10-2012, 11:10 AM
#33
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2012 S350 Bluetec 4Matic, Diamond White, P2
It is not the tires or temps that have the heavy impact on winter fuel mileage. It is the fuel itself. The winter blends have special addititives to accelerate vaporization in cold temps. These additives are resonsible for the biggest hit in fuel mielage during the winter months. The notorious winter blends are the most likley culprit to reduce mpg during the winter months.
