Gas Mileage and Ratings

That Solara (2 door Camry) probably had a big 2.5L 4 cyl also.

New Camry with the 2.5L 4 cyl can pull the OD gearing & has variable valvetrain like a lot of newer engines now days , and anyway Car & Driver

got 45 US MPG in their 75 MPH real world test.
 
I had an '04 Camry with the 3.3 v6
I'm not a heavy on throttle guy but cruise on hwys pretty quick 75+
Mixed did high 20s, (28?)
Highway 32.
Maybe the 2.4 was a bad match for some reason.
Maybe the 6 was geared lower?
 
Just an observation on sparkplugs.This is my long experience,and that of most of my buds running in similar circumstances.

NGK makes an excellent plug,so long as you use them in modern,fuel injected engines.If you install them in anything that generally runs on the rich side (basically anything with a carburettor) and uses an enrichment system for starting,such as a choke,or in the case of old British motorcycles,a ''tickler'' button,which simply allows you to manually push down on the float in order to flood the carb for starting,they die really quick. For whatever reason,if you run them rich,or get them wet,they never recover.You can wash them in solvent and clean them up all you want,makes no difference.They just don't like being gassed on.

For all of my injected engines,NGK all the way. All of my carburetted stuff gets Champion. And I ONLY buy my plugs,individually boxed,at the autoparts place.

And I am in full agreement on Bosch plugs (and most everything else that company makes these days) being absolute shit.Apparently the sun has set on the days of German excellence in engineering and manufacturing.Makes me ashamed to be a Kraut....:(

As for the fuel mileage ratings,I think they are full of crap. I have never owned any vehicle (new or used) that even came close to the advertised numbers,even under optimum conditions.All of my vehicles have been impeccably maintained.Mind you,they are either pickup trucks or full-sized sedans of the V8 variety.
 
... And I ONLY buy my plugs,individually boxed,at the autoparts place.

....

Some years back I bought a sleeve of plugs at the local auto parts store. Eight in the sleeve, individually boxed inside, for the good old V8 days.

Installed the first two plugs no problem. Pulled out the third from the sleeve, opened the little box, low and behold it was a well-used plug. As it turns out, so were the remaining five.

Apparently some low life bought the sleeve of eight plugs, used six, then returned them with the two unused ones first in line in case the auto parts store checked the box.
 
The gearing on the Solara was higher.

At 70 mph it was turning a lot more rpm's than the Grand Prix.

Just my thoughts.
That higher RPM on my 4-cylinder engines used to bother me, until I realized something...

At 70 MPH, my older 4 cylinders would run at 3000 RPM. A similar aged V6 would run around 2000 RPM at the same speed.

Now, figure out how many times the cylinders are firing over the course of a minute. 3000 RPM over 4 cylinders is 12,000 times per minute. 2000 RPM over 6 cylinders is....12,000 times per minute. Running a 4 cylinder on lower gearing would just bog it down, assuming that each cylinder were displacing a similar volume (a 2.0L 4-cylinder and 3.0L 6-cylinder would both have a volume of 0.5L per cylinder).

There are of course many other factors involved in determining the mileage, but just based on the number of times the engine is firing during a minute, they are in a sense equal in that regard. That made me fret less about the higher RPMs my smaller engines were running at.
 
Fusion is a longer wheelbase/longer overall & 500 lb heavier car also. My father bought a 2017 with the 1.5T , but is too new to really check MPG accurately & is now parked for the winter.

An engine is an air pump and if not treated right ( breaking it in or hard/fast driving before being warmed up) it can be less efficient. As you know design is an art also!

Oops I actually meant to say I drove a FOCUS not a Fusion. Focus is smaller and comparable to my new Civic.

At 25k when I bought the car, I'm dependent on the original owner for break-in...no way to control that. Price you pay for getting an almost new car a lot cheaper than a new one.

That Solara (2 door Camry) probably had a big 2.5L 4 cyl also.

New Camry with the 2.5L 4 cyl can pull the OD gearing & has variable valvetrain like a lot of newer engines now days , and anyway Car & Driver

got 45 US MPG in their 75 MPH real world test.

Surprised to hear that! Camry is in the midsize (Fusion/Accord) class and is doing far better than my compact Civic.

CVT's may not be very efficient either or not always work right!

I kinda wonder about that. The CVT in the Civic acts differently from other cars I've driven with regular AT's so I don't know what 'correct' is. It does seem to stay at low rpms at a certain point when accellerating. but I don't know whether it's supposed to do that or not. Doesn't exactly bog down but one would think the engine would rev in 2d-3d gear when getting on the highway and not sit there at 1500-2000 rpm. I'm not flooring it, maybe I should try putting my foot in it and see if it responds. If not maybe there is something wrong with it. Cruising at highway speed, it runs steady at 2500 +/-.
 
I kinda wonder about that. The CVT in the Civic acts differently from other cars I've driven with regular AT's so I don't know what 'correct' is. It does seem to stay at low rpms at a certain point when accellerating. but I don't know whether it's supposed to do that or not. Doesn't exactly bog down but one would think the engine would rev in 2d-3d gear when getting on the highway and not sit there at 1500-2000 rpm. I'm not flooring it, maybe I should try putting my foot in it and see if it responds. If not maybe there is something wrong with it. Cruising at highway speed, it runs steady at 2500 +/-.
That is normal for a CVT. Some call it a "rubberband effect", although Honda in recent years programs their CVT to act more like a traditional automatic with "speeds" or "gears" so it is not like earlier CVTs that would drone on at a constant RPM as vehicle speed increased. A CVT is, in the simplest of terms, two variable speed pulleys, a steel belt, and a computer which controls everything to operate in an optimal range (trading off power vs. gas mileage more efficiently than other transmissions). The 2017 Civic I drove had a slight rubberband effect, but otherwise it acted like a traditional automatic. Especially when I punched the throttle and the turbo kicked in--the revs would jump up, and we'd be nailed back into the seats from the boost. ;) The only time I really noticed a slight rubberband effect was if I was doing a very light throttle acceleration, where the revs stayed pretty much the same but speed increased.

Some (most?) Honda engines have an "idle learn" procedure, and some have commented that the gas mileage has improved afterward. (It involves resetting the CPU, then running the engine while parked under certain conditions.) That might be worth looking into.

You might also check with a dealer to see if there have been any software upgrades for engine/transmission. It's a slim possibility though.
 
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Honda and Mazda's CVT's are the smoothest I've ever driven. Can't ever feel the gear change, unless you really punch it. I'm a MT guy and both of those were a surprise.
 
If your Civic is anything like mine then you will most likely need to keep the ECON button engaged at all times to reasonably get to or beat the EPA ratings. My average is roughly 33-34mpg, 36mpg if I feather foot it but with the ECON engaged I can easily do 39 mpg+....too bad the ECON button sucks all the life out of the engine. It's also interesting that automatics are more efficient than manuals now, I had an automatic version of my car as a rental and getting 36mph felt a lot more effortless with the CVT.
 
I've run a few tanks (maybe 8) through and kept track but not with the ECON button - yet. Observations so far:

1. I'm getting 30-35 mpg in mostly highway driving. Respectable but not the 35-40 I expected.
2. Temperature does have a real effect. During weeks when it was very cold, mileage went down maybe up to 5% or even more.
3. My top speed does have some effect - when I drove 65 vs. 75 it made a measurable difference although not a lot.
4. The mpg readout on the dash is generally within +/- 0.5 mpg of what I calculate when filling the tank. At some point I will stop bothering with calculations and rely on the readout.

Soon I'll drive it for a tank (about a week of going to work) with the ECON button on the entire time and see how it does.

I do notice that 'rubberband effect' most when accelerating slowly. It does fine when I punch it, so it's not that big a deal.

I got in the mail the other day a letter from the dealer about the warranty on my Certified Used Car. I didn't buy it as a Certified Used Car with a warranty - it was 'as-is, no warranty.' :dunno: But I'll take it! :bigok:
 
I recently departed with a 5 speed 2005 Civic SE. It got 40 Mph pretty consistently at 65 mph.

Our legal speed limit is 80 mph, changed about 2 or 3 years ago. At 80 mph my gas mileage drops to about 35-36, especially if there is a wind. Winter also affected economy.

I've only had my 2012 CRV a couple of weeks, but it is running about 29-30 at 65mph according to the display. When I go 80, it drops.

I haven't tried turning ECON off to see what happens.

FYI - ethanol laced fuel has never been near my '83 Yamaha XJ550, which is why I believe it is still running really well to this day.
 
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Our legal speed limit is 80 mph, changed about 2 or 3 years ago. At 80 mph my gas mileage drops to about 35-36, especially if there is a wind.
Aaah, you were the slowpoke we passed on I-90 last summer. :D

I've only had my 2012 CRV a couple of weeks, but it is running about 29-30 at 65mph according to the display.
That's pretty good for a V. We have pretty much the same K24 engine--yours is just a newer version of it. I think I mentioned it earlier, but I only saw a gradual drop-off in gas mileage between 70-80, which surprised me. Once I'd get above 82 though, the mileage would take a big hit--seems like 80-82 was the tipping point for me. I was really hammering it through SD--that's, shall we say, not exactly the most efficient tankful I had on that trip. ;)

At fill-up time, the mileage indicator was usually within 1 MPG either way of what I calculated at the pump.
 
Thought I should report on the warm weather performance of my 'new' 2015 Civic since I whined about it in the winter after I bought it.

Hot weather makes a big difference. Where I was getting 32-33 all winter, now I'm getting 35-38. Last weekend we took a road trip (350 mi one way) and had a tailwind plus temps in the 90s on the way out and got 40.8 mpg on the first tank. Note, I'm running the AC much of the time too. I was surprised how much of a difference temperature makes.

Now my question is, just for science, is this caused by A) lower aerodynamic drag since hot air is thinner, B) warmer air coming into the engine increases combustion temps and boosts fuel efficiency, C) the tires have less friction at hotter temps, or D) some other effect I haven't accounted for, or E) a combination of several factors?
 
Fuel formulations may be better in the summer and warm temps do help. Winters are a lot colder here so you do notice even more of a difference because you have to warm the engine to defrost the windows. I don't think aero would make much difference to notice (but who knows!) and tire pressure and tire type (some winter tires may be worse) determines MPG.
 
Hotter air actually reduces combustion efficiency. Its less dense, so less actual oxygen in there. Needs less fuel to light, but makes less power as well. One trick hypermilers occasionally use is a "hot air intake". Instead of pulling air from outside of the engine bay, they build a shroud around the exhaust and feed the engine hot air so it leans out the fuel mix. Same idea as carb vehicles with the manifold stove to warm up the air charge in the winter.
 
One trick hypermilers occasionally use is a "hot air intake". Instead of pulling air from outside of the engine bay, they build a shroud around the exhaust and feed the engine hot air so it leans out the fuel mix. Same idea as carb vehicles with the manifold stove to warm up the air charge in the winter.

That sure beats drafting behind a semi running 80-90mph down the interstate!
 
My dinasaur of a 67 Belair averages 20.8 mpg's in all around driving and I'm damn happy it does that well with its 283 V8 and 2 speed Powerglide tranny. I've put almost 10,000 miles on it in the last 4 years but most of that is a 25 mile drive each way to my local golf course. Will be heading there today in about 2.5 hours.
 
Impressive mileage for a '67 V8. :thumbsup:

Makes sense about the hot air being less dense, but I thought that's what mass-flow sensors and engine control computers were for? I guess you can't fight physics.
 
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