HWDRX

Hello everyone,
I am somewhat new to the forum. Posted a couple of times and visit often to read up. First off, about me, since this matters. I live in South Florida, I drive the 2012 Rx450h AWD, I am 47, male and am an average driver, not too fast and not too slow. I try to get the most mileage but not to the extent of Hyper mileage types. I work in the car and drive all day in it. Suffice to say it is my office. My habits are 20 percent highway and the rest surface roads. South florida surface roads are riddled with traffic and lights. I do about 2,000 per month on my cars. Finally, I use premium gas and it's about 90 degrees here currently, my tires are at 34 PSI cold. With that said, you now have a reference on which to base the next section.

I bought the RX with the expectation that it would get nearly the gas mileage that was posted on the sticker. I am aware that the manufacturer does not make this up, the govenrment does. This would be about 28 MPG all around. At first the truck was getting 27 mpg as calculated on fillup, not on the display. After some time the numbers kept dropping. At 3,500 and currently 4,100 miles the actual MPG was somewhere around 24-25. Meanwhile, I am on the forum reading about others blowing past 30, although nobody mentions if they have AWD. Nevertheless, it is somewhat annoying. Within the last day I thought that I might bring it in to see if the dealer can help.

As of today, and still sort of annoyed, I began to play with the car. One big thing I noticed is that if I shut the air conditioner off the car redirects power from the air conditioner to the drive system. In my case, on level road going about 45, if I have the air on full then shut it off as I monitor the display between the gauges, you can clearly see that the power is redirected. I think, HUM, could this be how others are doing so well? I then take it further and reset the average fuel meter. Go figure, the mileage jumps to levels I have never seen before. Running averages over 40! Of course I know that is not possible and not going to attempt to fool myself or anyone else. So I go and do the exact same thing, on the exact same road, except this time the air is on. What do you know, the reading is 26 MPG! Really!!

Now I am thinking about how others are getting the 30 MPG out of the car. Seems to me if you live just about anyplace north of Orlando you very likely have cool mornings, something we do not have here. You can flip your air off and crack the windows and make it to work without running the air, thus saving a great deal of money. Does anyone have something to add? Has anyone else noticed this?

If so, has anyone else tried to fiddle with the air to get the best combination of cooling and cost advantage? I am aware that recirculate is the best but if you have not noticed, I am full of hot air and the car interior gets stale quickly. Just curious as to what others are seeing.

Thanks,
Ed

Lexmex

I live in Miami and can't add much else to this. My commutes are generally early morning (leaving just before 7) and going about 10 miles or so one way (up the Palmetto Expressway northbound) and going back around 5 the same way.

Best advice is to keep your foot at a constant level on the accelerator (human cruise control is what I like to call it).

One other little trick I learned in Mexico from the 1/4 mile track was to throw water on the radiator area before starting the vehicle up (don't try that at a U.S. 1/4 mile track) and that would help the air conditioning run a cooler once you are out on the road).

Like most others down here, I do crack the windows open a bit to let any hot air out.

Other thing I also do is have my tire pressure a bit higher. For instance, on my tires the max is 44 psi, but I put them at around 38 summer and 39 winter (it varies and sometimes I don't bother, but I don't go below 38). Nitrogen does help here, so I don't have to fiddle with the pressure as often.

UCSB

Thanks for the observation, I will have to experiment with the AC unit a little. Here in N CA it is cool and AC could be off for most of my driving. I have the 450h FWD and I am a little bit of a hypermiler. Here is my take on my 450h. It is a 26 MPG car that you can squeeze 30 - 31 MPG out of if you focus on what you are doing (I run my tires at 32 PSI for comfort). On some outings I have gotten 36 MPG and even 44 MPG for shorter trips ... but, all big efforts. At 30 - 31 MPG (the AWD model will be lower), you can fit in with other traffic on the road. You are just going to be driving on the really conservative end of the scale. When I take my car out, I just decide how I want to drive it that day. If I just want to relax and have some fun, then I will just lower my expectations on MPG. I don't commute, but I have noticed that on the occasions where I am driving in fast moving traffic and matching my speed and driving style to other cars in the fast lane my mileage starts dropping into the 26 - 27 MPG range. I may just reset my expectations for the car to 26 MPG ... it is a lot more fun to drive in that range.

I have noticed that when I take my shoes off when driving, it will improve my gas and brake pedal touch and is good for 1 - 2 MPG ... plus it is more relaxing.

My brother drives 2K per month like you. In April, he picked up a Prius Plug-in. He is a crazy hypermiler and fixated on gas mileage ... but, he has been getting something like 290 MPG (he has high speed chargers at home and work). 290 MPG!!! Even factoring in the small amounts he paid to charge the car, this is just amazing. I think that someone using the car in a normal manner would easily get over 100 MPG. He does a lot of his miles as a single driver only in the car and has put a lot of nice touches in the car to make it very pleasant. When he upgraded to the Prius Plug-in, my daughter purchased his 2010 Prius. My daughter drives the car normally and has been getting 53 MPG overall (my brother used to squeeze 62 MPG out of the same car). After driving his new car around town the other day, it is pretty clear to me that it was the way to go for high mileage drivers. For in town driving, the sacrifices seem to be minimal in the car.

billy44bo

I am in LA (lower Alabama) the ac is one year round here. However, I do not see how the Electric AC has any effect on MPG with in town driving. The draw from the ac system on the traction battery would be made back up on braking and costing.

BertL

Simply FYI as a pointer in case someone has not seen it. This continuing thread over in the Hybrid sub-forum has had a lot of activity in recent weeks on a similar subject of MPG, why folks are or are not achieving expectations, etc. A couple other threads over there too on types of gas being used, etc that are exclusive to the 450h. Worth a look if folks have not seen those as well.

BobBass

HWDRX,

I live in Southeastern PA and have consistently averaged 22.5 in the winter and 23.5 in the summer on 10% ethanol regular gas doing mixed driving, many short trips. I probably have a slightly heavier foot than the average driver. For me to achieve the EPA listing for my '08 400h AWD I'd have to creep along at the speed limit and mosey up to it to boot. That ain't gonna happen.

HWDRX

Hello again,
To follow up. Billy, try finding a long stretch of level road in Lower Alabama, if possible. Have the air on cold and reset the average MPG scale on the dash. Then switch over to the display that shows where the power is from. The display between the dials, the one with the battery and engine. Drive at a steady 40-50 MPH and watch. You will notice the power coming form mostly the engine. Check your Average MPG and make a mental note. Now reverse the route. Do the same thing but this time turn off the air alltogether. Yea, it's hot here too! Don't forget to reset the Average MPG before you do this. Now switch back to that engine / battery display and drive. Do the same speed. Watch how the power from the battery goes to the drive vs. not with the air on. After your done be sure to check your average. If like me, you should see a rather large bump in averages. I did this a couple of times as I thought, no way, this can't be right. I was able to repeat the results. Averages went from about 26 to over 40. Of course I could not run around with the air off, I would melt!

Interestingly, just after I posted Saturday I was running around for the day. I set the air to 77 degrees and auto. It still cools about the same. It seems that the average MPG went right back up to what I was getting when I bought the thing! HUM, could the air be that much of a drag on fuel consumption. Oh, and something else. I notice when I have that air cranking the motor seems to run a great deal more even though the traction battery is fully charged.

If anyone has a chance to try these things please report back. I would love to hear what happens.

Thanks,
Ed

HWDRX

That 10% junk is here too. What a bill of goods! I wonder if anyone did a study comparing the amount of fossal fuel we are saving vs. what we loose in fuel economy, would they pull the stuff off the market? I suspect not. Too many deep pockets. One day I am going to pull non ethanol gas out of my boat and put it in the RX and see what happens.

Ed

wa3cuj

You will find that your mileage increases. We use to be able to get ethanol free gas at 1-2 places around here, and when I would use it, my mileage would go up by about 2 mpg per tank. Those places have stopped selling it because they had to charge more for it and people were only comparing the cost to fill versus the cost/mile to drive.

A local TV station did a consumer report where they compared the percentage of ethanol in fuel at various stations, and the results were all over the place -- some being considerably over 10%!! So if you ever wonder why one tank seems to be getting much less mpg than you are use to, you may have gotten a tank with a higher percentage of ethanol.

If you are a corn producer, I guess there might be more money in growing corn for use as a fuel additive versus growing corn to feed people. I'm not so sure that remains true if you take away the government subsidies, which is simply borrowed money that our kids and grandkids will have to pay back some day!

hypervish

If your looking for a gas station that offers ethanol free gas, check out this website: http://www.pure-gas.org/

You will see an increase in fuel economy, and power. And, they will be noticeable on the butt dyno. lol

DunWkg

The Ag Economy is well beyond a discussion here, but if you have an interest here is an old article as a primer:

http://www.ers.usda.gov/amberwaves/f...cornprices.htm


Now back to the initial post, Ed have you run the car in ECO mode and made an evaluation of the effect of ECO versus Normal on mileage and air conditioning?

2011RX350

Straight gasoline will help fuel economy. Ethanol reduces mpg but does drive up food prices. Premium does nothing for mpg. 3 or 4 more psi tire pressure would help. A nervous foot on the throttle, constantly changing, will hurt your fuel consumption. That's about all you have control of.

rxsuperman

Here is a mileage data point: On my 2011 RX350 AWD, I achieved 28.5 MPG driving from New Jersey to Virginia with A/C on AUTO averaging 60 to 65 MPH.

dctex99

Likewise with a FWD and driving slower; I just cannot justify a Hybrid unless it gets A LOT better gas mileage and I drive it to work every day; even than the excessive cost is a concern; glad I don't have to worry about it. I will drive around with 10 cases of flashlight batteries at the very latest I ever have to.....lol!! I hate green!!

BobBass

rxsuperman,

If you AVERAGED 60-65mph that's darn good mileage in a RX AWD. I assume there must have been some long segments >70mph.