Somewhat disappointed

[Lafiro]

Originally Posted by YarisOwnersDad

Thanks, Woody.

Isn't it true that whenever the switch is in the defrost position, the A/C compressor is on? If so, then we might as well have cold air and be comfortable, right?

I could be wrong about that. Woody, or anyone else, is what I said above true or not?

Tomster

Yes, the a/c is engaged and the a/c is on, even if its hot air. The cold coils remove all the humidity from the air.

Maybe with the defrost option set, the a/c does not stay engaged as often as if the a/c was turned on, on purpose? Thus it will be on less of the time, saving on gas?

I really can't say, don't know if anyone could answer that one correctly either.

[b_hickman11]

Originally Posted by supmet

I've lived in wisconsin, and my mom lives in chicago. Dew point/humidity is only really an issue because you are creating a difference in temperature between the water molecules in the air and your windshield.

edit: I've pretty much driven the gamut of humidities, from death valley and vegas to the midwest. The A/C has never been "required" to keep the windshield from fogging. You're making a cold windshield with the A/C, which INCREASES condensation. Having a windshield the same temp as the outside air creates the least amount of condensation, regardless of humidity.

I can you never been to Texas. With 100% humidity the windows will fog up from your breath. So it's not always caused by just using the ac.

[Woody_Woodchuck]

That is exactly why my windows are down a little, to circulate air. In the summer it is what I do right after getting in, before the key is in the ignition. It seems easier to prevent it from happening than to clear it up after the fact.

I can relate it to winter driving up north. You were either a cold windshield person or a warm windshield person. Granted some days you had no choice but to defrost all the ice. I was a cold windshield guy. Cold windshields would not melt falling snow and therefore not ice and not need scraping unless the roads were slushy and splashing on the windshield. Any fresh fallen snow could be cleared with a brush or the wipers. Just keep the vent window open (yeah, this was a while ago) to circulate your breath and prevent fogging. Run the defroster on low and cold to prevent warming the windshield. Warm folks would need to run the defroster and anytime they stopped for more than an hour because the precipitation would freeze and need to be scraped and defrosted. Any water vapor in the car would be drawn to the colder windows and need to be scraped.

[Kaotic Lazagna]

Seems pretty good to me.

[roadrunner]

"Isn't it true that whenever the switch is in the defrost position, the A/C compressor is on? If so, then we might as well have cold air and be comfortable, right?"

If the lowest knob is on cold, and the middle knob is on defrost, and the top knob is off, NO AIR IS RUNNING.
If the lowest knob is on cold, and the middle knob is on defrost, and the top knob is 1 or higher, THE AIR IS RUNNING.

[Lafiro]

As long as the knob isn't on the defrost position, or the a/c botton is pressed, the a/c compressor will not engage when the fan is turned on, like you said roadrunner, setting 1 and up, lol.

You can purposely leave them both on that position, but leave the fan on 0/off, and the a/c compressor will never engage.

But, I do wonder though, why is it as soon as you switch the dial to hot, within seconds, if you have the vent's open, you will feel the hot air. And if you change it back to cold, it will almost immediately switch back to cool air/outside temperature or inside for that matter.

Maybe someone could help me understand how the heating works, and what happens with the car when the dial is turned to the red for heat.

[1stToyota]

Originally Posted by YarisOwnersDad

I just returned from a trip in which I logged 962.2 miles on 23.735 gallons of gas, for an overall average of 40.54 MPG. I was expecting higher MPG than that, since it was almost entirely Interstate cruising.

OK, tell me if you think I should have done better on MPG given these facts:

1. The car is an 09 Yaris sedan with auto tranny

2. I used the A/C all the time on this trip.

3. I keep my tires at the recommended cold inflation pressure and do not over-inflate to get higher MPG.

4. I had two 44 lb sacks of dog food that I picked up early in the trip in the back seat. (I would not be coming back through the town where the pet food shop was located during regular business hours, so I had to pick up the dog food at the front end of my trip and carry it around in the car for the rest of the trip.)

5. I used cruise control set for between 65 and 70 MPH, depending on where I was.

6. The car had about 7500 miles on it at the start of the trip.

So, do you guys think I got the MPG that I should have expected to get under the conditions as described above, or should I have gotten higher MPG?

I really thought that I would get 44 or 45 MPG.

Yes, I know I could have slowed down to 55 MPH and gotten way better gas mileage, and I could have done this or done that, but that is not the question. I'm only asking for opinions about whether or not I got the MPG I should have gotten for the conditions I have listed.

Tom

Seems low to me.

I drive 65-70 mph everyday

Tires always @ 32 psi

A/C used everyday this summer

Haul about 45 lbs of dachshund and tools around everywhere I go

Round trip to work is 45 miles, mostly highway, with 11 of those miles being city driving, with 17 stop signs or lights to deal with, and I average between 41-44 mpg all the time, unless I buy crappy Phillips gas during the winter and then I'll go below 40 mpg.

[YarisOwnersDad]

Yeah, I didn't think 44 or 45 MPG would have been too much to expect under the conditions I listed. Take away your 11 miles of city driving, and you would be up in that range.

Tom

[R2D2]

Hang in there Tom! Our Yarii are young and breaking in! My Yaris is putting up better and better numbers all the time. The folks getting big numbers have some miles under their belt and I'm convinced this is a big factor. Upping the tire psi to 44+ also makes a big (and free!) difference.

If you can get an ecometer or scan gauge they can really help "train" your driving for best mpg. These things + eliminating idle time are the biggest factors IMO.

R2

[1stToyota]

Originally Posted by YarisOwnersDad

Yeah, I didn't think 44 or 45 MPG would have been too much to expect under the conditions I listed. Take away your 11 miles of city driving, and you would be up in that range.

Tom

I could probably do it with a SC or Kiwi meter, just change my driving habits a bit...I'd still always stick with 32 psi though, for my old bone's sake, and the fact that the vehicle's placard says so...even the fine printing on my Eagle LS sidewall says don't over inflate or under inflate and to follow the placard recommendation, so that's what I do.

[R2D2]

Originally Posted by Lafiro

oh,
I just changed my oil to 5w-20 royal purple with k&n filter. I will also be pushing the PSI up to around 40. Lets see what happens in the next few tanks!

Just curious if you meant K&N oil or air filter?

Royal Purple 5W-20 is a very good choice IMO-very good TBN retention if your going to extend your drain intervals.

R2

[YarisOwnersDad]

It's all a matter of priorities.

Those who place MPG at the top of the list feel that it is worth it to increase tire pressure, slow way down, shun the use of their air conditioners, and use all of the tricks to maximize MPG. That's fine, if that's what they want to do, and no one should tell them that they are wrong to do those things.

In my case, however, I am only willing to do my best to get good MPG while maintaining the recommended inflation pressure in my tires, driving the posted speed limits, using my A/C when it's needed for my comfort, and slowing down well ahead of time when approacing a red light, so that I might not even have to stop before the light goes green, and the stopped cars have moved on.

Maybe I will never see the mid 40s for MPG on long trips or break the 40 MPG barrier on my daily commute, but I know how I could do it, if I ever change my priorities.

I was just thinking that I might have hit 44 or 45 MPG on my recent trip, even driving the way I did, but it didn't happen. Not a biggie. As has been said in this thread already, nothin' wrong with 40.5 MPG.

Tomster

[Lafiro]

Thats pretty much it. I memorize roads, stop signs, and stop lights, so I almost never have to stop much, but like I said, city driving kills everything, and stop and go on the "highway" is never helpful.

Oh, that K&N filter was oil. Still using stock type air filter. Don't know if it will help if I change that out for something else. If so, please let me know because it needs to be changed within the next oil change.

Actually I was really surprised, I filled my tank yesterday, mind you I only changed to 5w-20 recently, inbetween this tank. And I got an average of 30.5mpg!!!!! For me thats great to see for the conditions I see.

[R2D2]

The only air filter besides the stock dry fabric I would run would be the AFE Pro Dry. I bought one for my wife's Rogue and it is of outstanding quality. It cleans by vacuuming to (claimed) 96% of it's original airflow. They are available from Auto Anything and maybe other places. I haven't decided if I'm going to get a Pro Dry or just change my OE style often. The OE looks like a pretty good design IMO.

I'm not comfortable with oiled media due to the risk of MAF contamination-though some have used them without apparent issue.

The K&N oil filters are of excellent quality and have a great reputation +RP should be a great combo for you.

R2

[b_hickman11]

Originally Posted by R2D2

The only air filter besides the stock dry fabric I would run would be the AFE Pro Dry. I bought one for my wife's Rogue and it is of outstanding quality. It cleans by vacuuming to (claimed) 96% of it's original airflow. They are available from Auto Anything and maybe other places. I haven't decided if I'm going to get a Pro Dry or just change my OE style often. The OE looks like a pretty good design IMO.

I'm not comfortable with oiled media due to the risk of MAF contamination-though some have used them without apparent issue.

The K&N oil filters are of excellent quality and have a great reputation +RP should be a great combo for you.

R2

Or you can save a bunch of money and just use the Super Tech filter from Wal-Mart. They are a lot cheaper and made by the same folks that make the K&N.

[R2D2]

You are correct-last I knew both were made by Champion Labs. However that is where the comparison ends. Cut them apart and you will see what I mean.

R2

[b_hickman11]

There was a link with pics on here a while back where someone did just that and there wasnt much difference between the 2.

[Lafiro]

Might as well take two or three layers of screen mesh (the kind to keep the bugs out), and use that as an air filter....... lolol