2016 = 35mpg

http://www.businessweek.com/autos/autobeat/archives/2009/05/obama_wants_35.html

now if that doesn't bring diesels here in North America I don't now what will

Mazda has stated their intent to do so.

But, I suspect that improvements in gasoline engines will offset the diesel efficiency advantage. Take a look at the 2011 Hyundai Sonata for one good example, and Hyundai is going to be replacing the Accent and Elantra soon, with direct-injection engines across the board. They could very well be the first auto manufacturer to have direct-injection engines available in every model.

Personally, I'm in favor of "whatever works". The direct-injection gasoline engine situation seems a bit strange right now. Some manufacturers (notably Hyundai and to some extent VW) have figured out how to get good efficiency out of those engines, others (notably Mazda and to some extent GM) have not. Others (VW in North America, Ford Ecoboost) are only using it in oversized high power output applications where the efficiency benefit is not apparent.

I've expected gasoline and diesel technologies to converge to a large extent. Diesels get expensive and lose some of their efficiency when you make them meet current emission standards. Gasoline engines get expensive when you do stuff to make them approach the efficiency of a diesel but so far the market has mostly used this technology to get more power (mostly unnecessarily - who really needs 270 hp in a minivan?) rather than better efficiency.

It's all good. I like the 2011 Sonata, but I also like that GM is putting direct-injection 4-bangers in Equinox and the upcoming Buick Regal, and that we're finally going to be getting small cars that aren't penalty boxes.

The problem the DI gas engines have (and often it is horrible) is intake valve deposits. You no longer have a consistent spray of gas on the backsides of them like you do with port injection, so they get gunked up. And since most of these engines are multi-valve and have teeny weeny little intake valves, when they gunk up they can really cause some BAD driveability problems. Toyota is having so many issues with the DI GR engines (among other problems with that POS engine family) that they are replacing the valve springs with stronger ones because the gunk gets built up so much so bad that it will hold the valves open .

Running them hard helps, as well as no short trips, but otherwise frequent intake decarb cleaning (induction cleaning) is the only solution. And I have seen and heard of some of these cars needing this at intervals as frequent as every 15k miles.

Couple that with the teething problems some of the high pressure fuel systems that go along with DI means that there is still a lot of room for improvement. But I agree it is a great idea, and has many benefits.

Let's not forget that VW has already gone through (and fixed) the intake-clogging situation with the TDI diesels!

Personally, I wonder when someone is going to figure out that they might be able to get most of the benefit of direct-injection, but still be able to wash the valve stems, by putting the injector in the intake runner but really close to the intake valves (mounted in the head, rather than in the intake manifold well upstream of the head). It also gets the injector out of being exposed to combustion-chamber conditions.

What is yall's opinion on the body and under components of the hyundai and kia"s? Price wise with the options they come with they LOOK like a good deal. I do not really live in the snow belt but had a girlfriend with a kia and my daughter has a sportage. They seem cheap and disposable. The rust they get under them is terribile compared to domestics and Vw's. I do however have issue with a Jetta now costing nearly 30K.

Damn, our ML recently got 32 mpg...Oh so close maybe after it breaks-in?

GoFaster said:

Gasoline engines get expensive when you do stuff to make them approach the efficiency of a diesel but so far the market has mostly used this technology to get more power (mostly unnecessarily - who really needs 270 hp in a minivan?) rather than better efficiency.

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Why do you hate 'murica HP sells to the dumb *ss Americans.

There is a twist to that: It's not MPG, but a tailpipe output, and the reduction of air conditioning gas leaks counts towards reducing the emissions, too.

"The regulations set a goal of achieving by 2016 the equivalent of 35.5 miles per gallon combined for cars and trucks, an increase of nearly 10 miles per gallon over current standards set by the National Highway Traffic Safety Administration. The figure could actually be as low as 34.1 miles per gallon because automakers can receive credits for reducing greenhouse gas emissions in other ways, including preventing the leaking of coolant from air conditioners."

And since it's "tailpipe emissions" biodiesel users can't claim the greener-than-thou mantle of using crop growth absorption of atmospheric CO2, but plug-in electrics, even if powered by high sulfur soft coal, get a no "tailpipe", so no emissions ruling.

LiLredTDI said:

What is yall's opinion on the body and under components of the hyundai and kia"s? Price wise with the options they come with they LOOK like a good deal. I do not really live in the snow belt but had a girlfriend with a kia and my daughter has a sportage. They seem cheap and disposable. The rust they get under them is terribile compared to domestics and Vw's. I do however have issue with a Jetta now costing nearly 30K.

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Go rent one. Get insurance. Drive it into a telephone pole at 15mph.

Get any other kind of car in the same class and repeat.

You won't ant the Kia/Hyundai after you see the test results.

Unfortunately, it should not take a Government mandate to achieve the obvious --- less fuel used equals less dependence on oil. The question is whether one will snub the good for the perfect as is what typically happens and hence nothing gets accomplished.

Yes, I would imagine that you will see more turbos; more cylinder shut down features; and smaller displacement engines coupled with whatever type of injection hits that mark as people cling to their gasoline technologies (do to the failure of this Country's education system ). It also means more hybrids and more diesels. But then again, one must remember that VW achieved this mpg mark and then sum in the 1980s ......

There have some cars for years that have achived big numbers in fuel economy. They were not glamorous but got great mileage. Examples: ford escort zxII(5 spd.), tercel(5 spd.), corolla(5 spd.), K-car(even the automatic), acclaim(automatic), all VW 1.6' diesels. I'm sure there are more.

I have owned all of the above cars usually briefly and they all could get 30+ if driven conservitivly. The k-car and acclaim were cheap to buy even with low mileage cause they were very undisireable but were reliable and got great mileage, and could easily seat 4 people.

oilhammer said:

The problem the DI gas engines have (and often it is horrible) is intake valve deposits. You no longer have a consistent spray of gas on the backsides of them like you do with port injection, so they get gunked up.

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Where is the gunk coming from? Without a fuel spray from wet runners, there should be nothing but clean air passing the intake valves. Is it EGR deposits?

kcfoxie said:

Go rent one. Get insurance. Drive it into a telephone pole at 15mph.

Get any other kind of car in the same class and repeat.

You won't ant the Kia/Hyundai after you see the test results.

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I dunno. Maybe they make them weak especially for the US but here they do just as well as other brands in EuroNCAP.

LiLredTDI said:

There have some cars for years that have achived big numbers in fuel economy. They were not glamorous but got great mileage. Examples: ford escort zxII(5 spd.), tercel(5 spd.), corolla(5 spd.), K-car(even the automatic), acclaim(automatic), all VW 1.6' diesels. I'm sure there are more.

I have owned all of the above cars usually briefly and they all could get 30+ if driven conservitivly. The k-car and acclaim were cheap to buy even with low mileage cause they were very undisireable but were reliable and got great mileage, and could easily seat 4 people.

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The K-car, chryslers rolling sludg-o-matic, pos, death-trap? It is a testament to why they deserve to be out of business forever. I enjoyed the thrill of trying to merge having the pedal mashed through the floor as a semi came up my rear since the car took 5 minutes to accelerate from 26 mph to 45 mph. I would rather walk .....

MrMopar said:

Where is the gunk coming from? Without a fuel spray from wet runners, there should be nothing but clean air passing the intake valves. Is it EGR deposits?

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Sure, as long as the engine is running. What happens to an intake after you shut the engine off? Why do you think port-injected cars get their upper intakes and throttle plates gunked up?

All the leftover half-burned HCs and crap floating around in that (at least) one cylinder with its intake valve left open seeps back up into the intake and collects on the relatively cool intake plenum and over time builds up.

But in the case of the port injected engines, when you start them up again at least some level of cleaning happens to the backsides of the intake valves as the fuel injectors mist gasoline on to them, especially under hard acceleration where the fuel REALLY sprays out hard. The DI cars have no such cleaning affect, so they gunk up just like the rest of the plenum does.

LoL........Chill big Arnie : )..........Just saying they got great mileage, were cheap, could seat 4 many years ago. they were not that bad, just ugly.

oilhammer said:

Sure, as long as the engine is running. What happens to an intake after you shut the engine off? Why do you think port-injected cars get their upper intakes and throttle plates gunked up?

All the leftover half-burned HCs and crap floating around in that (at least) one cylinder with its intake valve left open seeps back up into the intake and collects on the relatively cool intake plenum and over time builds up.

But in the case of the port injected engines, when you start them up again at least some level of cleaning happens to the backsides of the intake valves as the fuel injectors mist gasoline on to them, especially under hard acceleration where the fuel REALLY sprays out hard. The DI cars have no such cleaning affect, so they gunk up just like the rest of the plenum does.

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I thought that when you kill the ignition, it kills the fuel injection in addition to the ignition. Wouldn't the engine turn over a couple revolutions and pump out any excess exhaust? That would cycle in clean air, and leave nothing to dirty the intake.

Could a person rev the engine up a bit, to about 2,000 RPM, and then kill the ignition? That would make sure the engine pumps quite a bit of clean air through it before coming to a halt. I used to do that with my Mazda RX-7 if I had to move the car without warming up the engine sufficiently. To keep it from refusing to start (with gasoline washing down the apex seals, and preventing compression on the next start) I used to rev the engine up to about 5,000 RPM with a throttle blip before turning the ignition key off - and that always worked fine.

No, does not work that way.

Go out and run your Accent.... then shut it off and immediately take the air intake boot loose at the throttle body and open the throttle up manually.... an oily, smokey mist will come back out of the intake. And I bet even your brand new car already has some gunk on the backside of the throttle plate.

GoFaster said:

Let's not forget that VW has already gone through (and fixed) the intake-clogging situation with the TDI diesels!

Personally, I wonder when someone is going to figure out that they might be able to get most of the benefit of direct-injection, but still be able to wash the valve stems, by putting the injector in the intake runner but really close to the intake valves (mounted in the head, rather than in the intake manifold well upstream of the head). It also gets the injector out of being exposed to combustion-chamber conditions.

Click to expand...

I don't see how this solution gives you the benefits of direct-injection. Isn't the efficiency gain in a spark-ignition engine due to a higher compression ratio? This requires direct injection to avoid detonation. If the fuel is injected prior to the intake closing, you can't run that high compression ratio.

You can still time the squirt to achieve stratified charge ...

oilhammer said:

No, does not work that way.

Go out and run your Accent.... then shut it off and immediately take the air intake boot loose at the throttle body and open the throttle up manually.... an oily, smokey mist will come back out of the intake. And I bet even your brand new car already has some gunk on the backside of the throttle plate.

Click to expand...

Interesting. I'll take your word for it.

How do you prevent this, or how do you clean it regularly? Is there a spray or fogging type of cleaner that is good for this?

BG (and others) have induction cleaning systems for these. Work great!

GoFaster said:

You can still time the squirt to achieve stratified charge ...

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Google the BMW 'N 54" the twin turbo direct injection L6.
The european version does use stratified charge under cruise conditions. They can't do it in the US, to many different gasolines. It runs a very high compression ratio for a forced induction engine. The coolant pump is variable speed electric so the coolant temp varies depending on demand (210*f = econpmy, 180*= power).

The problem is with gas at or under $3 per gallon, why would someone want to buy one? The only good way to do it is raise gas taxes every year, and let the marketplace determine the acceptable MPG. Government should not mandate mileage or the technology to get it, they need to provide consumers with the proper incentive which will fuel demand for economical cars. Look at Europe-no minimum mileage requirements, but $7 per gallon is the reason they get the cool 60 MPG diesels we can only dream about. Too bad Americans don't know how fun diesels are to drive.

That is a big jump to add 10 mpg avg to the fleet in a short amount of time. The goverment must think it so easy to get better mpg.I guess they want everyone to drive a smart car the death trap.What is mpg on them?

33 & 41 for the smart hard top, and it requires premium gas. Every time I see one of those things I half expect a bunch of circus clowns to jump out and start running around.

I have a smart car and there is nothing unsafe about them, we were lucky in Canada we got the turbo diesel. I get 80 plus miles per gallon on long trips and 70 plus around town. Every thing is related to mass, when I drove highway rig I would kill every one in a VW if I had ever hit one so VW are death traps. On the good side there are a couple around that are clowns, they drive a diesel Passat. They put on shows for kids.

Thunderstruck said:

33 & 41 for the smart hard top,

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Thus why I can't help but call it the Dumb Car when my Passat does 45 with my wife's lead foot... Now with the diesel it is a different story as red2002 points out.

Jack_Berry said:

diesel was effectively killed in the 80's by american car makers.

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Diesel was abandoned by American car manufacturers after the 80s because of a combination of a huge glut of oil on the market, leading to low prices for about 20 years, and new CAFE regulations that let US auto makers game the system with the SUV era.