mmarshall

After an absolutely miserable winter, and record or near-record snow in in many parts of the country, temperatures are finally climbing somewhat and staying there. With the spring, of course, go some noticeable changes with your car...mostly positive, I'm glad to say.

Although the rising sun angle, warmer temperatures, and longer days do mean that you'll want to keep the car and/or interior surfaces covered more often when parked, the warmer temperatures and sun do help in other ways. Air pressure in the tires goes up; generally 1 PSI for each ten degrees of air temperature. So, the chance of having underinflated tires goes down somewhat, especially in older cars without tire PSI-monitoring devices. Tires sitting in the sun (which often happens on one side of the car) will, of course, be warmer than the rest, because the black color of the rubber absorbs a lot of UV rays, which warms them up even more....they will show an even higher PSI. Despite the added tire PSI (which would otherwise stiffen up the ride), the car will usually ride smoother on a warm sunny day, simply because the rubber in the tires softens up with the sun and heat, allowing more flexibility and bump-absorbtion. This increase in ride comfort on warm sunny days is especially noticeable with a lot of today's low-profile tires, which otherwise, in my opinion, can be unacceptably stiff. In some cases (not all), despite the added ride-comfort, even handling and braking can improve at the same time, because the warmer, softer rubber in the sidewalls and warmer pavement temperatures on the road means added grip on the road and makes the tires less likely to slide. The black rubber weatherstripping and sound-insulation also expands in the heat and forms tighter seals and more effective sound-deadening, cutting down on wind noise (and sometimes on road noise).


Under the hood, positive changes also take place. Starting/warm-up is quicker and easier because engine oil is thinner and flows better (though today's low and multi-viscosity oils also help). Oil pressure generally comes up to normal quicker. The warmer start-up temperature means that the fuel-injectors can deliver a leaner mixture during the warm-up, cutting fuel use. The transmission and its fluid warms up quicker, allowing the car to get into the higher gears sooner (some automatics block out certain upshifts at colder fluid-temperatures). You usually won't hear as much of that annoying tick-tick from the engine's lifters (if applicable) when cold, because the warmer engine oil lubricates them better during warm-up. And, of course, if you consolidate many of your short trips, the engine won't cool down as rapidly when you park and are inside doing your errands as in the winter, when it is subject to more warm-up/cool-down cycles. Warm drive-belts and pulleys under the hood are less likely to squeak or make annoying noises. And last, the underhood fluids are less likely to deteriorate over time because the fluids stay warmer and evaporate or burn off contaminants like water, acids, dirt, etc....

So, enjoy the warmer temperatures and the (mostly) positive changes they bring to your car. Of course, you car owners in Southern California are already one step ahead of some of the rest of us......you get to enjoy that most of the year.

doge

Seems like the gas stations here in Chicago are back to serving the summer blend of fuel. I've noticed 3mpg increase on my Buick! However the amg is as miserable as ever.

TangoRed

All I can think about is the reduction in the amount of new potholes I will encounter on a daily basis.

FrankReynoldsCPA

I'm already way ahead of you :P

I used my A/C on the way to work this morning.

Window tint is coming.

mmarshall

Yes, fuel-blends, because of EPA regulations and/or the CARB (California Air Resources Board), will vary in parts of the country with the season, in general, as temperatures climb, so does fuel mileage. Some mileage, though, is lost because of the EPA mandate to mix a 10% blend of ethanol in many places. There's no way around that, gas stations usually have to sell it that way, and the 10% mixture (E10) usually applies year around.

The gas mileage drops off with ethanol mixtures because alcohol, though burning cleaner than gasoline, has a much lower energy BTU content than gasoline (roughly 40 per cent). So, the more they mix it, the lower the average fuel-mileage usually is with it. Ethanol, over time and with repeated use, can also damage a regular gas-powered car's fuel system if used in concentrations over 15% or so (E15). There is currently a political fight over whether the EPA will (or should) be allowed to mandate E15 nationwide. Auto manufacturer warranties usually cover fuel system damage at up to E10, but not E15....though some of the very newest ones can handle E15 without problems. Some American-designed engines (particularly from GM) can safely run E85 (85% ethanol), which is widely available in the Midwest Corn Belt, but not in other parts of the country....but, of course, with that much ethanol in the blend, fuel-mileage will drop drastically. My Buick Verano, though designed primarily for E10/15, has an E85-rated engine, as do many current GM vehicles and some of those from Chrysler.

mmarshall

In Vegas, though, they can get a little too much sun and heat during the warmer months. That, of course, doesn't do the car much good when it's 115 degrees outside and the sun in coming through the windows.



Yep...if I lived in a desert area like that, I'd also consider tint...and a car cover. But first check the law in Nevada on that one....allowable shades of tint can vary by state and on individual windows, and police can issue citations for it.

mmarshall

FYI, if you're interested, I've already covered many of the pothole issues in another Car Chat thread.

https://www.clublexus.com/forums/car...-your-car.html

mmarshall

As if they aren't already expensive enough to start with, some AMGs get such lousy mileage they get slapped with a Federal Gas Guzzler Tax on their price sticker.

robert1408

Great post, mmarshal! I'd like to add a few other benefits of warmer weather concerning fuel economy.

Warm tires not only ride better but they also have significantly less rolling resistance.

Warmer air is less dense so aerodynamic drag is reduced. Assuming a constant barometric pressure, air density is a function of absolute temperature (kelin). Figure about a 10% reduction in air density (and resultant drag) for each 47 degree F increase. This reduction in drag is easily more than enough to compensate for using the AC.

While ethanol in our fuel is a given these days, warm weather and higher altitude blends have a lesser portion of lighter volatiles to reduce vapor pressures (evaporation). This reduction of volatiles leaves you a slightly denser (higher specific gravity) fuel with a bit higher BTU content. This helps your fuel economy some,too.

mmarshall

Thanks. It's just a few things I've noticed over the years, from experience.

Depends on the road surface. On a smooth, non-porous surface, tires will often have more grip on the pavement in warm weather, which means more friction and more engine power required to turn them. On more porous surfaces, though, as you note, resistance is less of an issue.


Correct. Warm air also means fuel is vaporized better, allowing a leaner mixture. But it also means less horsepower from the engine because less fuel is burned in the cylinders.

This, BTW, can also make a significant difference in aircraft (I am also a rated Private Pilot and Ground Instructor). In warmer weather and higher altitudes, longer runways are needed for safe take-offs, landings, obstacle-clearance than at sea level or lower altitudes. That's because the less-dense air with warmer temperatures and/or higher altitudes lessens the amount of power that both piston and turbine engines can make (compensated to an extent, with turbos/superchargers), thrust that propeller-blades can produce, and the lift that wings and flaps can generate.

I'm still a little concerned, though, what will happen with some engines if the EPA legally mandates E15 and car-owners are stuck with it on non-rated engines. Auto manufacturers will probably not cover any fuel-system damage from it, except on maybe the E85-rated engines that GM and Chrysler produce. I say that EPA is going to force E15 down our throats, then let THEM pay for new engines or repairs if needed.

FrankReynoldsCPA

Frankly, the EPA does not give a ****. Your typical granola would love nothing more than to see older vehicles forced off the road, no matter the cost to the owner. Look at the increased costs diesel owners have had to bear as a result of regulation. The DPF filters have destroyed economy and the regeneration required to clear them has a tendency to do damage to the engine. The ultra-low sulfer diesel that is now required doesn't lubricate the moving parts of the fuel system nearly as well as the older fuel, and it's causing premature wear on fuel pumps.

The EPA does not see the individual as somebody who needs their vehicle and can't afford significat retrofits or replacement. They see you as somebody who is destroying the atmosphere and need to be reformed at any cost.

Fortunately my Ford has an E85 flex-fuel engine. I've searched for ethanol-free fuel in Vegas, but it looks like there are none to be had here. Fortunately it's just E10 though, not E85.

mmarshall

Believe it or not, there was actually an attempt to do that some years ago with so-called Crusher-Laws. A car, regardless of the number of miles on its odometer, had to be taken off the road and run through a crusher after a certain amount of time. Public resistance (including, of course, classic-car organizations) got that stopped. Later, the Obama Administration passed the well-known Cash-for-Clunkers program, where the Federal Government compensated dealerships for accepting trade-ins and giving BIG discounts to owners who traded in older/less-efficient vehicles for newer/more efficient ones. The program, while somewhat successful in the short term, ended up a mess. Many perfectly good, still-usable vehicles were taken off the road, the engines deliberately destroyed or recycled (as required by the program), and the endless bureaucratic paperwork needed for the government payoffs held up a lot of the government reimbursements.

And don't forget those urea-solution refills every 10-15K miles....they are needed on many (but not all) of the newer and BlueTec diesels. Some diesel manufacturers make it a selling point by covering those refills in a free-maintenance program.



Yes, E10 is still officially the norm in most places...but we (still) may have at least the possibility of EPA-mandated E15 coming. My Verano, like your Ford, has an E85 engine...they are probably going to be the norm pretty soon for internal-combustion vehicle engines.

And, thanks for the info, BTW. I knew that GM and Chrysler did some E85s, but I wasn't sure about Ford.

tmf2004

iTrader: (15)

Good thread Mike... thanks ....... Here in FL though i would like 70 degrees year round lol...

LexFather

I think these tips are relevant for older cars, not new ones...with technology today everything has changed...

Tire pressures do still change though! Unless you use Nitrogen which many cars use today...

FrankReynoldsCPA

I know a lot of people in the older truck crowd were affected by this. Parts in junkyards became much harder to obtain because so many of them were earmarked for destruction. It was illegal to salvage or sell any parts from a clunker. Talk about waste.


To be fair, the new urea SCR system is a redeeming factor on the new diesels. It is a passive system that performs a lot of the same function of the EGR, without the harmful effects that EGR has on diesel engines. As a result of it, the DPF becomes less clogged and needs to be cleaned less often. It actually has contributed to a slight increase in MPG over the 07 emissions. BUT the system overall is still more complicated and expensive than the pre-07 diesels...a lot of people have switched to gas because of it.



Yeah, Ford added E85 capability to the 3.0 Duratec with the 2010 revision of the Fusion. I don't know if the 4 cylinder ever got it.

They also threw in that weird capless fuel filler with the change. The first few times I stopped to fill up I thought I'd left my cap somewhere.