Mile Per Gallon

[CrunchySkippy]

You'd be wise to stay out of it. The old brake dust thread has a flame or insult in almost every post. Things like that are cumulative. It's not up for discussion though since no power has been exercised and therefore has not been abused.

Have a problem? Take it to PM.

Stick to the topic here.

Are you kidding me??? Sounds like you're threatening me now!

Get over yourself, Bartkat. Nobody even mentioned the "old brake dust" thread here, except for you.

Nice advice about sticking to the topic. You've done a tremendous job following your own advice.

[bartkat]

Have a problem? Take it to PM.

[Randy&Bonnie]

Guys... this is a very interesting topic for discussion. It's pertinent. It deserves some messaging. Let's discuss it with decorum and facts. *decorum button off* Just from what I've read, several of you are pulling stuff out of your butts. *decorum button on*

FACT: The temperature of the ambient air WILL effect "power" which in turn effects fuel consumption. And, it's most likely measureable. Unless and until someone can show me some believeable data that says otherwise.... I'll standby and read what you automotive "geniuses" come up with.

[smooth1]

LOL!!!

This is great!

Ok, so of all the things you listed, you came back with the tire pressure issue and the boutique fuels. Are you conceeding the other points then?

And btw, your dispute about the fuels.......You never thought to ask if the OP was going to the same fuel station or not, so again, your point with that is moot. He could be fueling up with E85 for all we know at this point. And he did say that for the last 6 months, which would mean that the summer or winter mix thing is not pertinent at all in this. But we can continue to involve that fact in our debate if you would like.

Check the drag journals on the 350, it's not an insignificant difference in power... air temp has been shown to have a larger impact on drag times than nearly anything else anyone has done to the car so far.

I don't disagree with this statement, the problem here is that the lower temp also improves the grip of the tires, along with the engines ability to produce more hp. We can't really gauge which as more of an influence on the times, but the bigger issue is that all the drag times posted don't include the amount of fuel used to acheive those times. Which is the topic here. If I produce more hp and use the same amount of fuel, I have improved the efficiency of the motor, but not the fuel mileage. You would still burn the exact same amount of fuel.

In your tire pressure issue, while I understand your point of the temp. effecting the psi, it's more about the psi in the tires effecting fuel mileage, not the temp itself. Underinflated tires can easily be remedied in any outside temp. situation. You can still run underinflated tires in hot weather and have the same effect on fuel mileage.

The IAT measures the air temp coming in, the MAF measures the amount, the H02S measures the results of the combustion, and it all adjusts accordingly. But the 14.7:1 ratio never really changes. We aren't talking about the 14.7 part, we are talking about the 1. That 1 is allways 1 for every combustion stroke, unless it's altered by a smaller fuel injector, recalibrated at the ECU, or fuel flow is restricted somehow. How much power that cumbustion stroke makes is a byproduct of that 1.

Colder air =more oxygen = more fuel gets added= less foot input on the throttle to acheive the same power.

Hotter air = less oxygen = less fuel gets added= more foot input on the throttle to acheive the same power.

It's an offsetting equation. We all prefer the more power part, but agian, the fuel consumption is the same! And if someone brings up the "cold air intakes" argument, that would really prove they have no clue! While some aftermarket intakes do help improve engine efficiency by reducing the air restriction, and making the intake tubing more smooth and less turbulant, they have little to do with "cooling" the intake air, and again, while they may help create more power, they do not reduce the amount of fuel consumed.

[smooth1]

FACT: The temperature of the ambient air WILL effect "power" which in turn effects fuel consumption. And, it's most likely measureable. Unless and until someone can show me some believeable data that says otherwise.... I'll standby and read what you automotive "geniuses" come up with.

I think some people are confusing a MAP system with a MAF system. In a MAP system, the timing and A/F ratios are all programmed to follow a ridgid program based on a set of values established for each stage of throttle positions and rpm in the ECU, or, for those a bit older and remember carburated engines. So, in a system like that, any change to one of the contributing factors such as air temp can have an effect on the amount of power the engine can make and hence run leaner or richer, as the fuel amount will remain constant, unless manipulated directly. In other words, the engine doesn't self adjust as it is following a preset program. I've only seen this system used in aftermarket though, and mostly used for forced induction applications as technology has long since changed for the production car market. They all run MAF systems now that all self adjust. Maybe some systems aren't as good as others at adjusting, but that is a completely different conversation. In this case, since the amount of fuel is NOT changed due to the intake air temp, which means you have changed the A/F ratio, then you would see an improvement in fuel mileage due to the air temperatures. But in this case you would see an improvement in colder air, not warmer, as the amount of power being produced would result in less throttle input, but also remember, in this case you would be running a leaner A/F ratio and that could be dangerous for the motor. So there is a trade off.

[Knightshade]

So in other words, my original claim was:

Cars get better mileage in warmer weather (summer) rather than colder (winter).

And you agree with me.

Thanks for the clarity.

Not sure how I'm "conceding the other points" since they all remain true... oil and such are thicker in colder temps, this more friction, thus more fuel to run the engine until they warm up in the motor.... 100% true point.

Cars get worse mileage on winter blend fuel, without tracking where each and every person gets their gas from we can assume that on average each station sells "about" the same to the same amount of customers, even if which is which changes a bit... so on average mileage in winter is worse due to the less-energy fuel...100% true point.

Every 10 degrees of colder temps drops tire pressure 1 lb, and underinflated tires are bad for fuel economy. 100% true point. You don't want to overfill the tires when icy cold because eventually (though it takes a while) if you're taking a longish trip the tires will heat back up.

And by the way, since you skipped over this point entirely, even modern cars run in open loop mode longer in the winter (since it takes longer to reach operating temp), and it gets worse mileage in this mode since it's running richer. That, on top of the tire issue, the winter blend issue, and the others, all contribute to the worse winter mileage compared to summer. 100% true point.

So the only wrong in the thread so far was your insistance I was wrong, and giving a lecture about IAT and MAF systems, which had nothing to do with anything I originally said.

Just so we're nice and crystal clear.

[smooth1]

So in other words, my original claim was:

Cars get better mileage in warmer weather (summer) rather than colder (winter).

And you agree with me.

Thanks for the clarity.

Not sure how I'm "conceding the other points" since they all remain true... oil and such are thicker in colder temps, this more friction, thus more fuel to run the engine until they warm up in the motor.... 100% true point.

Cars get worse mileage on winter blend fuel, without tracking where each and every person gets their gas from we can assume that on average each station sells "about" the same to the same amount of customers, even if which is which changes a bit... so on average mileage in winter is worse due to the less-energy fuel...100% true point.

Every 10 degrees of colder temps drops tire pressure 1 lb, and underinflated tires are bad for fuel economy. 100% true point. You don't want to overfill the tires when icy cold because eventually (though it takes a while) if you're taking a longish trip the tires will heat back up.

And by the way, since you skipped over this point entirely, even modern cars run in open loop mode longer in the winter (since it takes longer to reach operating temp), and it gets worse mileage in this mode since it's running richer. That, on top of the tire issue, the winter blend issue, and the others, all contribute to the worse winter mileage compared to summer. 100% true point.

So the only wrong in the thread so far was your insistance I was wrong, and giving a lecture about IAT and MAF systems, which had nothing to do with anything I originally said.

Just so we're nice and crystal clear.

Oh we are crystal clear alright. Everything you have listed so far effects other things that may or may not effect fuel mileage. Nothing you have listed has anything to do with the temprature or summer vs. winter directly effecting fuel mileage. as everything you have listed can be said no matter what the temprature or time of year. HOW you drive your car will effect fuel mileage. The physical attributes of the vehicle will change and fluctuate no matter what time of year or the outside temprature. So again, your point is moot. But you can continue to think your right.

[Knightshade]

So in other words, my original claim was:

Cars get better mileage in warmer weather (summer) rather than colder (winter).

And you agree with me.

Thanks for the clarity.

Not sure how I'm "conceding the other points" since they all remain true... oil and such are thicker in colder temps, this more friction, thus more fuel to run the engine until they warm up in the motor.... 100% true point.

Cars get worse mileage on winter blend fuel, without tracking where each and every person gets their gas from we can assume that on average each station sells "about" the same to the same amount of customers, even if which is which changes a bit... so on average mileage in winter is worse due to the less-energy fuel...100% true point.

Every 10 degrees of colder temps drops tire pressure 1 lb, and underinflated tires are bad for fuel economy. 100% true point. You don't want to overfill the tires when icy cold because eventually (though it takes a while) if you're taking a longish trip the tires will heat back up.

And by the way, since you skipped over this point entirely, even modern cars run in open loop mode longer in the winter (since it takes longer to reach operating temp), and it gets worse mileage in this mode since it's running richer. That, on top of the tire issue, the winter blend issue, and the others, all contribute to the worse winter mileage compared to summer. 100% true point.

So the only wrong in the thread so far was your insistance I was wrong, and giving a lecture about IAT and MAF systems, which had nothing to do with anything I originally said.

Just so we're nice and crystal clear.

Oh we are crystal clear alright. Everything you have listed so far effects other things that may or may not effect fuel mileage. Nothing you have listed has anything to do with the temprature or summer vs. winter directly effecting fuel mileage. as everything you have listed can be said no matter what the temprature or time of year. HOW you drive your car will effect fuel mileage. The physical attributes of the vehicle will change and fluctuate no matter what time of year or the outside temprature. So again, your point is moot. But you can continue to think your right.

Every item I listed is directly effected by weather. Every item directly impacts fuel mileage.

Fluids cause increased engine friction when it's colder. That'd be temp related. More friction reduces mileage.

Tires drop 1 psi per 10 degrees. Temp related. Lower inflation is more rolling resistance, reduces mileage.

Open loop uses more fuel, and it's in open loop longer when it's cold out because it takes longer to reach operating temp. Temp related. Using more fuel for same distance traveled is worse mileage.

It's help when trying to claim someone is wrong if you, ya know, made any sense in doing so or offering a single reason why. Give that a shot.

[Randy&Bonnie]

FACT: The temperature of the ambient air WILL effect "power" which in turn effects fuel consumption. And, it's most likely measureable. Unless and until someone can show me some believeable data that says otherwise.... I'll standby and read what you automotive "geniuses" come up with.

I think some people are confusing a MAP system with a MAF system. In a MAP system, the timing and A/F ratios are all programmed to follow a ridgid program based on a set of values established for each stage of throttle positions and rpm in the ECU, or, for those a bit older and remember carburated engines. So, in a system like that, any change to one of the contributing factors such as air temp can have an effect on the amount of power the engine can make and hence run leaner or richer, as the fuel amount will remain constant, unless manipulated directly. In other words, the engine doesn't self adjust as it is following a preset program. I've only seen this system used in aftermarket though, and mostly used for forced induction applications as technology has long since changed for the production car market. They all run MAF systems now that all self adjust. Maybe some systems aren't as good as others at adjusting, but that is a completely different conversation. In this case, since the amount of fuel is NOT changed due to the intake air temp, which means you have changed the A/F ratio, then you would see an improvement in fuel mileage due to the air temperatures. But in this case you would see an improvement in colder air, not warmer, as the amount of power being produced would result in less throttle input, but also remember, in this case you would be running a leaner A/F ratio and that could be dangerous for the motor. So there is a trade off.

Hi Smoothie,

While I read and understand what point you are trying to make, there are only so many "tricks" the little ECU can pull out it's little chip butt. It can only "fool" the charge in the combustion chamber so long!

If my IS250 is running down the freeway here in sunny AZ at 100d F and 10% RH and it's getting xx MPG, then I beam myself and my IS250 (way too expensive to drive!) over to Billings, Montana - ambient air temp is 30d F and RH 10%, will I see the same MPG - assuming both Phoenix and Billings are the same elevations? B)

[smooth1]

FACT: The temperature of the ambient air WILL effect "power" which in turn effects fuel consumption. And, it's most likely measureable. Unless and until someone can show me some believeable data that says otherwise.... I'll standby and read what you automotive "geniuses" come up with.

I think some people are confusing a MAP system with a MAF system. In a MAP system, the timing and A/F ratios are all programmed to follow a ridgid program based on a set of values established for each stage of throttle positions and rpm in the ECU, or, for those a bit older and remember carburated engines. So, in a system like that, any change to one of the contributing factors such as air temp can have an effect on the amount of power the engine can make and hence run leaner or richer, as the fuel amount will remain constant, unless manipulated directly. In other words, the engine doesn't self adjust as it is following a preset program. I've only seen this system used in aftermarket though, and mostly used for forced induction applications as technology has long since changed for the production car market. They all run MAF systems now that all self adjust. Maybe some systems aren't as good as others at adjusting, but that is a completely different conversation. In this case, since the amount of fuel is NOT changed due to the intake air temp, which means you have changed the A/F ratio, then you would see an improvement in fuel mileage due to the air temperatures. But in this case you would see an improvement in colder air, not warmer, as the amount of power being produced would result in less throttle input, but also remember, in this case you would be running a leaner A/F ratio and that could be dangerous for the motor. So there is a trade off.

Hi Smoothie,

While I read and understand what point you are trying to make, there are only so many "tricks" the little ECU can pull out it's little chip butt. It can only "fool" the charge in the combustion chamber so long!

If my IS250 is running down the freeway here in sunny AZ at 100d F and 10% RH and it's getting xx MPG, then I beam myself and my IS250 (way too expensive to drive!) over to Billings, Montana - ambient air temp is 30d F and RH 10%, will I see the same MPG - assuming both Phoenix and Billings are the same elevations? B)

While I read and understand what point you are trying to make, there are only so many "tricks" the little ECU can pull out it's little chip butt. It can only "fool" the charge in the combustion chamber so long!

It's not about "fooling" the combustion chamber. It's about maintaining the same amount of air mass.Oxygen has mass. That amount of mass can fluctuate in any given volume of air. Hence the MASS AIR FLOW SENSOR, not the VOLUME AIR SENSOR. Hotter air has less mass, and colder air has more mass. The mass reqiurements for the A/F mixture don't change. They are fixed. So is the size of your cylinder. The ECU will only allow the same amount of mass into the cylinder, no matter what the temp is. SO if the air is colder, the ECU will simply adjust to allow the same amount of mass into the cylinder. Now if you were to pressurize the cylinder, or force more VOLUME of air into the cylinder, causing the air to compact and warm, then return it to say an intercooler to further create more mass per volume of air it causing it to become more dense, but this is a completely different scenario as we are talking about forced induction. And in these cases, the MAF can never see "boost" conditions as it wil try to adjust and throw the car into "What the hell is going on!" mode. Natually asperated engines controlled by a MAF sensor reading ECU system, will be constant.

These newer fuel programs that Toyota and others are coming out with are designed alot differently than before. Let's not confuse some things. I am not saying NOTHING changes fuel mileage. I am only saying that the ambient temprature does not change the fuel mileage by itself. If we were to set up a controlled enviornment, with a motor on a bench, and measured power output and fuel mileage seperately, you would see the motor produce more or less power as the temp went up or down, but you would not see the fuel consumption rates change at all. We are talking about MPG. Not the effiency of the motor to produce HP. More HP doesn't translate to better fuel mileage. In that case, take a 3.5 liter, 1000 hp motor, while it is a very efficient motor as it can produce alot of hp per liter, more than most others, I don't get any more miles per gallon. This also explains why high miles per gallon vehicles don't have high horse power also. (Wouldn't that be great though?) It's allways a trade off.

[Knightshade]

Of course we're not discussing a motor on a bench.

In an actual car if you start the car in the winter in cold weather it will get worse mileage than an identical car started in warm weather in the summer.

Friction will be higher because the fluids will be colder, more fuel used.

The engine will take longer to reach operating temp so it will be in open loop mode longer and consume more fuel.

(and if the car actually moves anywhere on cold tires versus warm, assuming the same initial inflation at room temp, it'll get worse mileage from higher rolling resistance)

[smooth1]

Of course we're not discussing a motor on a bench.

In an actual car if you start the car in the winter in cold weather it will get worse mileage than an identical car started in warm weather in the summer.

Friction will be higher because the fluids will be colder, more fuel used.

The engine will take longer to reach operating temp so it will be in open loop mode longer and consume more fuel.

(and if the car actually moves anywhere on cold tires versus warm, assuming the same initial inflation at room temp, it'll get worse mileage from higher rolling resistance)

The open loop and closed operations no longer change the A/F ratios as in previous models. It used to be considered making the operation safer in an open loop, but no longer, so this isn't a variable anymore.

In an actual car if you start the car in the winter in cold weather it will get worse mileage than an identical car started in warm weather in the summer.

LOL!! No it won't! The ECU will just not send as much fuel to the combustion chamber! The engine will not be as efficient as when it warms up, but again, that doesn't translate to MPG's!!

[Knightshade]

Of course we're not discussing a motor on a bench.

In an actual car if you start the car in the winter in cold weather it will get worse mileage than an identical car started in warm weather in the summer.

Friction will be higher because the fluids will be colder, more fuel used.

The engine will take longer to reach operating temp so it will be in open loop mode longer and consume more fuel.

(and if the car actually moves anywhere on cold tires versus warm, assuming the same initial inflation at room temp, it'll get worse mileage from higher rolling resistance)

The open loop and closed operations no longer change the A/F ratios as in previous models. It used to be considered making the operation safer in an open loop, but no longer, so this isn't a variable anymore.

In an actual car if you start the car in the winter in cold weather it will get worse mileage than an identical car started in warm weather in the summer.

LOL!! No it won't! The ECU will just not send as much fuel to the combustion chamber! The engine will not be as efficient as when it warms up, but again, that doesn't translate to MPG's!!

So you're suggesting that an engine can run less efficiently without using more fuel?

What exactly do you think the word efficiently means?

Lemme try this as simply as possible... I'm fascinated to see how you can continue to give right answers and then reach totally wrong conclusions-

True or false- in colder weather the oil will take longer to reach operating temp?

True or false- the colder and thicker the oil is, the more friction in the engine?

True or false- the more friction in the engine the more fuel it require to run the same?

Can you point me to the Lexus technical info BTW that suggests the 2IS doesn't use open and closed loop mode like just about every other modern car on earth? Especially since guys who have actually scanned the ECU at work observe it using both open loop and closed loop anf the AF ratio changing between them? Thanks!

[Randy&Bonnie]

The mass reqiurements for the A/F mixture don't change. They are fixed. So is the size of your cylinder. The ECU will only allow the same amount of mass into the cylinder, no matter what the temp is. SO if the air is colder, the ECU will simply adjust to allow the same amount of mass into the cylinder.

Hi Smoothie,

1) The "mass requirements" for the A/F may be fixed, but in reality the A/F mixture fluctuates. Can the A/F mixture be different at idle than it is at 75 MPH?

2) Please explain how exactly the "ECU will only allow the same amount of mass into the cylinder, no matter what the temp is"?? Are you saying at 32d F ambient and 100d F ambient the A/F mixture will be the same?

[BaddBoi70]

Smooth and Knight -

You BOTH have valid points. But, the effects on MPG in all the scenarios (summer vs. winter) are simply insignificant with today's technology. It seems silly to debate this any further. Agree to disagree and let's move on.

If the discussion is of importance to both of you, then consider taking it offline or keep it private via PM.

[smooth1]

Of course we're not discussing a motor on a bench.

In an actual car if you start the car in the winter in cold weather it will get worse mileage than an identical car started in warm weather in the summer.

Friction will be higher because the fluids will be colder, more fuel used.

The engine will take longer to reach operating temp so it will be in open loop mode longer and consume more fuel.

(and if the car actually moves anywhere on cold tires versus warm, assuming the same initial inflation at room temp, it'll get worse mileage from higher rolling resistance)

The open loop and closed operations no longer change the A/F ratios as in previous models. It used to be considered making the operation safer in an open loop, but no longer, so this isn't a variable anymore.

In an actual car if you start the car in the winter in cold weather it will get worse mileage than an identical car started in warm weather in the summer.

LOL!! No it won't! The ECU will just not send as much fuel to the combustion chamber! The engine will not be as efficient as when it warms up, but again, that doesn't translate to MPG's!!

So you're suggesting that an engine can run less efficiently without using more fuel?

What exactly do you think the word efficiently means?

Lemme try this as simply as possible... I'm fascinated to see how you can continue to give right answers and then reach totally wrong conclusions-

True or false- in colder weather the oil will take longer to reach operating temp?

True or false- the colder and thicker the oil is, the more friction in the engine?

True or false- the more friction in the engine the more fuel it require to run the same?

Can you point me to the Lexus technical info BTW that suggests the 2IS doesn't use open and closed loop mode like just about every other modern car on earth? Especially since guys who have actually scanned the ECU at work observe it using both open loop and closed loop anf the AF ratio changing between them? Thanks!

So you're suggesting that an engine can run less efficiently without using more fuel?

What exactly do you think the word efficiently means?

Apparently it's you who needs the definition of efficiency. Because then you would have known to ask if we were talking about mechanical efficiency, thermal efficiency, volumetric efficiency, and so on, of which, none of them have anything to do with MPG. Which really shows it's your conclusions that are incorrect. Not mine.

True or false- in colder weather the oil will take longer to reach operating temp?

In which decade are we talking about? ( I thought you knew physics???) If you did, then you would know that oil lubricates the internal moving parts of the engine as they heat up and expand, causing thermal breakdown, which causes the moving parts to sieze and fuse together. The idea of "cold starting friction" went out with Teflon and PTFE resins in Slick 50, Duralube and the likes. So, False.

True or false- the colder and thicker the oil is, the more friction in the engine?

Are you implying that thicker oil creates more friction??? That's a ridiculous statement. So, false.

True or false- the more friction in the engine the more fuel it require to run the same?

This would pertain to mechanical efficiency. Mechanical efficiency is the percentage of energy that the engine puts out after subtracting mechanical losses such as friction, compared to what the engine would put out with no power loss. Most engines are about 90% mechanically efficient. Nowhere in any of those formulas are MPG's ever associated with it. So, False.

Can you point me to the Lexus technical info BTW that suggests the 2IS doesn't use open and closed loop mode like just about every other modern car on earth? Especially since guys who have actually scanned the ECU at work observe it using both open loop and closed loop anf the AF ratio changing between them? Thanks!

I never said that Lexus doesn't use an open or closed loop system. I said, that the theory behind using it has changed. Don't forget our cars use direct injection with cold injectors to suppliment light load conditions. It's a different system that enables the engineers alot more control over when the fuel is introduced to the combustion chamber. So the need to run richer fuel mixes is under more control than before. That's part of the reason why the 350 and other cars can now produce more hp, and still get the same gas mileage. But I'll see what I can do.

[smooth1]

My dad used to tell me:

"If your standing in a hole and you want to get out, stop digging!"

[Knightshade]

I agree, you should stop digging.

You keep making claims with backing a single one up.

And yet if you look around, everyone who knows cars will tell you cars get lower mileage in the winter.

I'm not sure what possible source could convince you, it took like 8 multi-degree professionals to convince you in the other thread.

How bout the guys from Car Talk? They'll tell you it's true too.

You seem to suggest thicker oil does -not- reduce mileage, here's the cartalk guys-

http://www.cartalk.com/content/features/fueleconomy/

"Thicker than required oil will also reduce your gas mileage, because it takes more energy to push through thick oil than it does through thinner oil."

Now, have you ever seen a bottle of motor oil?

If you have, it usually says something like 10W-30. Do you know why it has two numbers?

Do you know it has something to do with the thickness of the oil at different temperatures?

Some other things they have to say about winter mileage-

"Several things conspire to lower your mileage in cold weather. One is lower tire pressure. Even without any leaks, tire pressure drops about a pound for every 10-degree drop in temperature. So if you haven't checked the pressure since it was 80 degrees in the shade last summer, you may have lost enough tire pressure to seriously reduce your mileage."

"The other important change that occurs in the winter is that gasoline doesn't burn as well in cold temperatures. So you're not burning all of your gasoline completely. That means that some of it is being wasted in the cylinders, and that's hurting your mileage."

"This is particularly true if you make short trips, because the engine never gets out of the "warm-up" mode, where it boosts the idle speed and is pouring in extra gasoline anyway."

Now, again, if you have an actual -source- that proves the 2IS doesn't run richer in open loop mode before it reaches operating temp.... (not that it would discount the other points, or be any less true for all the other cars on the road) please provide it.

Or you can keep digging.

[Randy&Bonnie]

True or false- in colder weather the oil will take longer to reach operating temp?

True or false- the colder and thicker the oil is, the more friction in the engine?

True or false- the more friction in the engine the more fuel it require to run the same?

True, True, True!!!!!!!!!!! This is a "no brainer"..... 4th grade science!!

My name is Randy. I have 5 years of college and a 3-digit IQ, BUT.. ...I'm not smarter than a 5th grader!!

[lambobaby1218]

Smooth and Knight -

You BOTH have valid points. But, the effects on MPG in all the scenarios (summer vs. winter) are simply insignificant with today's technology. It seems silly to debate this any further. Agree to disagree and let's move on.

If the discussion is of importance to both of you, then consider taking it offline or keep it private via PM.

Seems they've ignored your suggestion.........

[BaddBoi70]

I agree, you should stop digging.

You keep making claims with backing a single one up.

And yet if you look around, everyone who knows cars will tell you cars get lower mileage in the winter.

I'm not sure what possible source could convince you, it took like 8 multi-degree professionals to convince you in the other thread.

How bout the guys from Car Talk? They'll tell you it's true too.

You seem to suggest thicker oil does -not- reduce mileage, here's the cartalk guys-

http://www.cartalk.com/content/features/fueleconomy/

"Thicker than required oil will also reduce your gas mileage, because it takes more energy to push through thick oil than it does through thinner oil."

Some other things they have to say about winter mileage-

"Several things conspire to lower your mileage in cold weather. One is lower tire pressure. Even without any leaks, tire pressure drops about a pound for every 10-degree drop in temperature. So if you haven't checked the pressure since it was 80 degrees in the shade last summer, you may have lost enough tire pressure to seriously reduce your mileage."

"The other important change that occurs in the winter is that gasoline doesn't burn as well in cold temperatures. So you're not burning all of your gasoline completely. That means that some of it is being wasted in the cylinders, and that's hurting your mileage."

"This is particularly true if you make short trips, because the engine never gets out of the "warm-up" mode, where it boosts the idle speed and is pouring in extra gasoline anyway."

Now, again, if you have an actual -source- that proves the 2IS doesn't run richer in open loop mode before it reaches operating temp.... (not that it would discount the other points, or be any less true for all the other cars on the road) please provide it.

Or you can keep digging.

Knightshade -

You have a lot of good insight, but your soapbox is quickly becoming far too large for this forum. I suspect the world would be a perfect place to live, if you were its ruler. I learned my lesson the hard way in the LOC. Take my advice now that I am offering below:

Stop berating others, agree to disagree, stop while you are ahead, learn from others advice, learn when to listen, stick to the facts, and most importantly - LOC is a place to discuss topics about our Lexus vehicles and to make friends NOT enemies!

Does it make sense to you that honey attracts more flies than vinegar? Or, will you want to debate me?

[Knightshade]

I agree, you should stop digging.

You keep making claims with backing a single one up.

And yet if you look around, everyone who knows cars will tell you cars get lower mileage in the winter.

I'm not sure what possible source could convince you, it took like 8 multi-degree professionals to convince you in the other thread.

How bout the guys from Car Talk? They'll tell you it's true too.

You seem to suggest thicker oil does -not- reduce mileage, here's the cartalk guys-

http://www.cartalk.com/content/features/fueleconomy/

"Thicker than required oil will also reduce your gas mileage, because it takes more energy to push through thick oil than it does through thinner oil."

Some other things they have to say about winter mileage-

"Several things conspire to lower your mileage in cold weather. One is lower tire pressure. Even without any leaks, tire pressure drops about a pound for every 10-degree drop in temperature. So if you haven't checked the pressure since it was 80 degrees in the shade last summer, you may have lost enough tire pressure to seriously reduce your mileage."

"The other important change that occurs in the winter is that gasoline doesn't burn as well in cold temperatures. So you're not burning all of your gasoline completely. That means that some of it is being wasted in the cylinders, and that's hurting your mileage."

"This is particularly true if you make short trips, because the engine never gets out of the "warm-up" mode, where it boosts the idle speed and is pouring in extra gasoline anyway."

Now, again, if you have an actual -source- that proves the 2IS doesn't run richer in open loop mode before it reaches operating temp.... (not that it would discount the other points, or be any less true for all the other cars on the road) please provide it.

Or you can keep digging.

Knightshade -

You have a lot of good insight, but your soapbox is quickly becoming far too large for this forum. I suspect the world would be a perfect place to live, if you were its ruler. I learned my lesson the hard way in the LOC. Take my advice now that I am offering below:

Stop berating others, agree to disagree, stop while you are ahead, learn from others advice, learn when to listen, stick to the facts, and most importantly - LOC is a place to discuss topics about our Lexus vehicles and to make friends NOT enemies!

Does it make sense to you that honey attracts more flies than vinegar? Or, will you want to debate me?

Honestly, I don't get the problem.

I've been a member here for nearly a year. Active the whole time. This past week is the first time I've posted a reasonable, true, easily verified fact, and had somebody go crazy trying to argue a point every expert on the topic agrees with. Twice. And it's not like I even started the thread or the debate either time.

I've been a member of other car forums for almost a decade, again without incident.

So I'm not real convinced I'm the problem.

I'll be happy to let this topic go to PMs with smooth1, and let everyone else do their own research on the topic. We'll see if he is as well.

[BaddBoi70]

I agree, you should stop digging.

You keep making claims with backing a single one up.

And yet if you look around, everyone who knows cars will tell you cars get lower mileage in the winter.

I'm not sure what possible source could convince you, it took like 8 multi-degree professionals to convince you in the other thread.

How bout the guys from Car Talk? They'll tell you it's true too.

You seem to suggest thicker oil does -not- reduce mileage, here's the cartalk guys-

http://www.cartalk.com/content/features/fueleconomy/

"Thicker than required oil will also reduce your gas mileage, because it takes more energy to push through thick oil than it does through thinner oil."

Some other things they have to say about winter mileage-

"Several things conspire to lower your mileage in cold weather. One is lower tire pressure. Even without any leaks, tire pressure drops about a pound for every 10-degree drop in temperature. So if you haven't checked the pressure since it was 80 degrees in the shade last summer, you may have lost enough tire pressure to seriously reduce your mileage."

"The other important change that occurs in the winter is that gasoline doesn't burn as well in cold temperatures. So you're not burning all of your gasoline completely. That means that some of it is being wasted in the cylinders, and that's hurting your mileage."

"This is particularly true if you make short trips, because the engine never gets out of the "warm-up" mode, where it boosts the idle speed and is pouring in extra gasoline anyway."

Now, again, if you have an actual -source- that proves the 2IS doesn't run richer in open loop mode before it reaches operating temp.... (not that it would discount the other points, or be any less true for all the other cars on the road) please provide it.

Or you can keep digging.

Knightshade -

You have a lot of good insight, but your soapbox is quickly becoming far too large for this forum. I suspect the world would be a perfect place to live, if you were its ruler. I learned my lesson the hard way in the LOC. Take my advice now that I am offering below:

Stop berating others, agree to disagree, stop while you are ahead, learn from others advice, learn when to listen, stick to the facts, and most importantly - LOC is a place to discuss topics about our Lexus vehicles and to make friends NOT enemies!

Does it make sense to you that honey attracts more flies than vinegar? Or, will you want to debate me?

Honestly, I don't get the problem.

I've been a member here for nearly a year. Active the whole time. This past week is the first time I've posted a reasonable, true, easily verified fact, and had somebody go crazy trying to argue a point every expert on the topic agrees with. Twice. And it's not like I even started the thread or the debate either time.

I've been a member of other car forums for almost a decade, again without incident.

So I'm not real convinced I'm the problem.

I'll be happy to let this topic go to PMs with smooth1, and let everyone else do their own research on the topic. We'll see if he is as well.

Knightshade -

Obviously, you wish to be combative when you use words like "argue". I'm trying to reach out to you b/c you have been a contributing member for a year :) Well, I tried. Good luck to you.

[Knightshade]

No, I wish to be accurate.

If you could possibly read this thread, or the other, and that not be the term that comes to mind about what folks are doing, well, I dunno what to tell you. I posted a simple, true, statement each time. Each time someone decided to argue about it.

How I'm being combative when I started neither argument remains equally unclear. Especially when I just offered to take the whole topic off-line if the other party does as well.

[Randy&Bonnie]

Smooth and Knight -

You BOTH have valid points. But, the effects on MPG in all the scenarios (summer vs. winter) are simply insignificant with today's technology. It seems silly to debate this any further. Agree to disagree and let's move on.

If the discussion is of importance to both of you, then consider taking it offline or keep it private via PM.

Badd,

I think you make a good stab at closing the discussion and it's admirable. And this discussion my need to be a "agree to disagree" thread. I do have a slight problem with spectator "censorship" injected into more intense discussions because it sometimes censors the real facts. If you don't like the "tone" then you don't have to read the thread. This site should have something for everyone, right? I don't read the ones that ask "what is my favorite color this or that"!

By the way, almost all of the threads on very controversial subjects get a little caustic. And yes, we are all adults and should be able to maintain our composures, but that's not reality. Unless the discussion is obviously getting so far off the subject by it's "tone", then I say let it go. Some of the very BEST discussions and most enlightening threads I have read are laced with very intense and heated debate.

Whether or not you may think that today's technology makes the MPG difference "insignificant" is irrelavent. The fact is that Knight's orginal comment that MPG is better in summer (warmer ambients) than in winter (colder ambients) IS TRUE.

The MAF senses the mass of the air intake and tells the ECU to "change" the A/F ratio, however, the MAF as a device, can not make the actual fuel consumption the same at different wide deltas of ambient temperatures.

That's just my worthless opinion.