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- RDX Aspec Adv.
I've used Mazda oil, and other oil, and there is ZERO difference in fuel economy.
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Very disapointing fuel economy from recent roadtrip...
- Thread starter buyingconstant7
- Start date
I've used Mazda oil, and other oil, and there is ZERO difference in fuel economy.
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- RDX Aspec Adv.
This is true, but for me the speed under which it gets excellent millage changes from drive to drive.
For example, on road trips, sometimes I'll get excellent mileage (33MPG+) at ~80MPH, but other times in seemingly identical conditions I'll be looking at ~27MPG at the same speed.
If I keep my speed ~70 the millage is always good, but sometimes it stays good even as I speed up. Other times it really goes down the toilet at high speeds.
I don't really know what causes this variation, but my best guess would be that sometimes the engine runs rich to prevent knock.
Some drivers (Unobtanium for example) likely frequently enter the "rich" operation parameters and are unhappy with their mileage while others do not.
I would really like to see proof of that under wide-band O2. That said, LS1 cars run PIG RICH and get their stated mileage at 75-80mph, as a datapoint. However, after manually calculating 28mpg for my last road-trip, I'm more irritated that the onboard computer sucks than I am about mileage. Minus 2mpg is not a problem at all for me, when the rating is 30. It's well within variance for wind,etc.
I would really like to see proof of that under wide-band O2. That said, LS1 cars run PIG RICH and get their stated mileage at 75-80mph, as a datapoint. However, after manually calculating 28mpg for my last road-trip, I'm more irritated that the onboard computer sucks than I am about mileage. Minus 2mpg is not a problem at all for me, when the rating is 30. It's well within variance for wind,etc.
I'd be more suspect about the gas pump meter used to calculate manually. Car's computer gets it data right from the ECU's fuel delivery calculation.
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- RDX Aspec Adv.
I'd be more suspect about the gas pump meter used to calculate manually. Car's computer gets it data right from the ECU's fuel delivery calculation.
I used GPS to track my route. The distance I went is accurate.
My wallet is what ultimately matters where fuel economy is discussed, and that pump dictates my wallet's pain.
The car's computer, in relation to the two, is way on back back way in the back of the peanut gallery, regarding the "worth" of its opinion, if that makes sense. Kindof like walking out in the cross-walk when you have the "Walk" sign and the oncoming semi has a redlight, when the semi-driver is not paying attention, and then somehow surviving while in a full body cast whining about "How did this happen!? I was RIGHT!"...tell that to your severed spine.
This is true, but for me the speed under which it gets excellent millage changes from drive to drive.
For example, on road trips, sometimes I'll get excellent mileage (33MPG+) at ~80MPH, but other times in seemingly identical conditions I'll be looking at ~27MPG at the same speed.
If I keep my speed ~70 the millage is always good, but sometimes it stays good even as I speed up. Other times it really goes down the toilet at high speeds.
I don't really know what causes this variation, but my best guess would be that sometimes the engine runs rich to prevent knock.
Some drivers (Unobtanium for example) likely frequently enter the "rich" operation parameters and are unhappy with their mileage while others do not.
If this is true, about "rich" operation, then it sounds like premium gas would prevent the "rich" operation and should give better mileage.
Has anyone tried this?
If this is true, about "rich" operation, then it sounds like premium gas would prevent the "rich" operation and should give better mileage.
Has anyone tried this?
I've tried it, but, honestly I can't get any reliable results.
I've gotten really excellent mileage on both grades of gas and I've also gotten mediocre mileage on both grades.
As MikeM used to always write, the engine is tuned for 87 Octane and it can automatically pull timing/fuel/valve closing/whatever based purely on environmental parameters and fuel maps (intake temp/barometric pressure/coolant temp ect.)
This automatic response to parameters isn't perfect, so in some rare cases (for example, lugging up a hill in 2nd gear at 1000RPM), the knock sensor and spark plug current sensing override the parameters set by the maps and here premium can possibly make a small difference.
I would really like to see proof of that under wide-band O2. That said, LS1 cars run PIG RICH and get their stated mileage at 75-80mph, as a datapoint. However, after manually calculating 28mpg for my last road-trip, I'm more irritated that the onboard computer sucks than I am about mileage. Minus 2mpg is not a problem at all for me, when the rating is 30. It's well within variance for wind,etc.
I agree. Some proof would be nice.
Keep in mind that the LS1 cars will get s*** for mileage just idling around town or sitting at a drive through. They certainly do well once at speed, but their highway rating gets (unfairly?) pulled down by their crappy low speed performance.
I wish the EPA would publish simple fuel economy numbers at various speeds instead of dumbing things down to 2 numbers.
I used GPS to track my route. The distance I went is accurate.
My wallet is what ultimately matters where fuel economy is discussed, and that pump dictates my wallet's pain.
The car's computer, in relation to the two, is way on back back way in the back of the peanut gallery, regarding the "worth" of its opinion, if that makes sense. Kindof like walking out in the cross-walk when you have the "Walk" sign and the oncoming semi has a redlight, when the semi-driver is not paying attention, and then somehow surviving while in a full body cast whining about "How did this happen!? I was RIGHT!"...tell that to your severed spine.
The only problem with measuring at the pump is that the "full" level of the tank is kind of random. It's not a problem if you track your milage in the long run cuz it'll average out, but for individual tanks you get a lot of variabiliy.
Sometimes I'll have zero fuel indicated on my gauge and only fit 12.5 gallons.. other times at zero it'll fit 13.3 gallons. 400/12.5 = 32MPG vs 400/13.3 = 30MPG
The only problem with measuring at the pump is that the "full" level of the tank is kind of random. It's not a problem if you track your milage in the long run cuz it'll average out, but for individual tanks you get a lot of variabiliy.
Sometimes I'll have zero fuel indicated on my gauge and only fit 12.5 gallons.. other times at zero it'll fit 13.3 gallons. 400/12.5 = 32MPG vs 400/13.3 = 30MPG
To measure at the pump one must go to the same gas station and the same pump and let that pump shut off by itself for both fill ups. This is not always possible.
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- 2016 Sport @ 2016.5 Sport
Just got back from 922 mile trip this weekend. We went from Syracuse to Elkton Md, Elkton to Selbyville DE and back to Syracuse. We averaged 27 MPG with the awd. The car was a gem to drive and handled extremely well. I was pleased with the mileage but thought the GPS always gave the worst routing directions. The only thing I liked about the factory GPS was that it told us where the red light cameras were.
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- RDX Aspec Adv.
I agree. Some proof would be nice.
Keep in mind that the LS1 cars will get s*** for mileage just idling around town or sitting at a drive through. They certainly do well once at speed, but their highway rating gets (unfairly?) pulled down by their crappy low speed performance.
I wish the EPA would publish simple fuel economy numbers at various speeds instead of dumbing things down to 2 numbers.
I dunno man, I averaged around 19mpg in my 6-speed WS.6, flogging the hell out of it as a college student. That's VERY SIMILAR to what my 370Z got even though it was lighter, geared stronger (better fore mileage in town), and had a V6 with only 2/3 the displacement and a ton more tech (no cams...each valve lifted by its own motor, tuned precisely) than my LS1. My LS7 (Z06) got around the same around town. By comparison, my WS.6 weighed more than my CX-5, and my CX-5 only gets around 22.5-23mpg around town...of course, I live in a different area, and I think that matters, too, but STILL. I have a lighter car with 1/2 the horsepower and it only gets 3mpg more? That's a crappy trade, if performance vs. mileage were ALL it was about.
The only problem with measuring at the pump is that the "full" level of the tank is kind of random. It's not a problem if you track your milage in the long run cuz it'll average out, but for individual tanks you get a lot of variabiliy.
Sometimes I'll have zero fuel indicated on my gauge and only fit 12.5 gallons.. other times at zero it'll fit 13.3 gallons. 400/12.5 = 32MPG vs 400/13.3 = 30MPG
I fill mine up until I can SEE the gasoline when I do measurements like this typically. I know, my car will explode because of this someday, but not today, apparently, lol
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- RDX Aspec Adv.
Just got back from 922 mile trip this weekend. We went from Syracuse to Elkton Md, Elkton to Selbyville DE and back to Syracuse. We averaged 27 MPG with the awd. The car was a gem to drive and handled extremely well. I was pleased with the mileage but thought the GPS always gave the worst routing directions. The only thing I liked about the factory GPS was that it told us where the red light cameras were.
Sounds identical to mine pretty much. I thought the 2016+'s got better something or other for hwy mileage?
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- RDX Aspec Adv.
To measure at the pump one must go to the same gas station and the same pump and let that pump shut off by itself for both fill ups. This is not always possible.
Fill it up until you SEE it. Even the same pump clicks off randomly it seems. But it's still not random enough to screw mileage calculation for a 500+ mile trip. Maybe by .25mpg or something max.
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- RDX Aspec Adv.
160 mile round trip today from Charlotte to asheboro and back. Mix of 55mph two lane and 65mph 4 lane highways. Drove right at the speed limit. 31.3 mpg average. Very very happy with the milage I'm getting with my AWD CX-5
That's typical for those low speeds. I think the complaint is that once you drive a normal freeway speed, it goes in the toilet, comparatively to the rating, and of that vs. other vehicles and their ratings which people have previously owned.
One thing I've noticed lately, and maybe this is known to others already, but this 90 degree, extremely humid weather is killing my gas mileage. Okay, not killing it but it is definitely worse ever since we've had this bump in heat and humidity. Today, I went to get crabs and about 40 min drive. Not highway, mostly 30-50 mph roads. On the way there, it was about 88 and I got 26mpg. On way home at 10, temperature was 74 and a lot less humid. Got 34mpg. Big difference! I know thereare other variables but temperature was a main one. I've been noticing a drop lately and thought it was maybe my recent oil change.
But I honestly am starting to think it's the temperature and humidity. I believe reading about this here and that the engine runs rich during hot weather to prevent knock. Maybe that'swhats going on here. This heat wave resulting in a reduction in my gas mileage. When nothing else has really changed.
But I honestly am starting to think it's the temperature and humidity. I believe reading about this here and that the engine runs rich during hot weather to prevent knock. Maybe that'swhats going on here. This heat wave resulting in a reduction in my gas mileage. When nothing else has really changed.
One thing I've noticed lately, and maybe this is known to others already, but this 90 degree, extremely humid weather is killing my gas mileage. Okay, not killing it but it is definitely worse ever since we've had this bump in heat and humidity. Today, I went to get crabs and about 40 min drive. Not highway, mostly 30-50 mph roads. On the way there, it was about 88 and I got 26mpg. On way home at 10, temperature was 74 and a lot less humid. Got 34mpg. Big difference! I know thereare other variables but temperature was a main one. I've been noticing a drop lately and thought it was maybe my recent oil change.
But I honestly am starting to think it's the temperature and humidity. I believe reading about this here and that the engine runs rich during hot weather to prevent knock. Maybe that'swhats going on here. This heat wave resulting in a reduction in my gas mileage. When nothing else has really changed.
Hot air is less dense. Humidity reduces available oxygen further. Pro drag racing will show this in greatly increased run times during warm weather vs more mild.
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