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Author Topic: Warming up the car Back to Topics
JamCoope
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Maryland

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Message Posted: Jan 26, 2011 10:21:52 AM

Most people agree that cars run more economically once they're warmed up... especially in the cold winter months.

Here's a question: has anyone tested whether it is more economical to let your car warm up by idling in the driveway, or by just letting warm up as you drive?
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dontuknowOH
Champion Author Ohio

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Message Posted: Mar 28, 2015 10:51:08 AM

I do know that on an average Winter temperature day, know that there is a big difference between two vehicles and the cost of warm-up.

My 4 cylinder that I have DIY modified somewhat warms quite well either idling or on the run, and I have usable cabin heat before 3 minutes of run time.

The V/8 vehicle DIY project also made a difference, but because of larger coolant capacity/engine size, different block metal composition and being a truck with more engine compartment roominess with better venting, the interval of engine warming is still longer. The V/8 engine response becomes better by working the engine harder with a load driving away.

If looking toward safety, I give the cost savings to be less for idling over the long term. I see way too many drivers on the move with snow pilled high on their vehicles, frost with peep holes scraped a few places to get glimpses of driving visible ability on the more severe days of Winter.

There is a dangerous cost waiting for that vehicle motion, lurking somewhere to happen. Running late makes it worse, but who ever does that?

With Our econos I don't see hardly much difference in the fuel use, to be worth the extra other risks of saving time/mileage for those days. I do both type of engine warming, depending on the conditions, also free all windows of Winter stuff before moving.
b899
Champion Author Connecticut

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Message Posted: Mar 28, 2015 9:12:29 AM

no
HotRod10
Champion Author Wyoming

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Message Posted: Mar 23, 2015 9:57:46 AM

"Work has a requirement that I sit and wait for the engine to warm up when it gets cold"

I wonder why they would do that? Could it be that they know something that many here are in denial about? Perhaps they realize that it's better for the engine and safer for the driver to allow the engine and glass to get warm before driving.
Godozo
Champion Author Gary

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Message Posted: Mar 22, 2015 11:15:43 PM

Only warm up my car when it's near 0 degrees Fahrenheit. Work has a requirement that I sit and wait for the engine to warm up when it gets cold (or the steering fluid starts sputtering out).
HotRod10
Champion Author Wyoming

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Message Posted: Mar 22, 2015 11:24:23 AM

spam1111: "Now i'm wondering if it was all wasted efforts."

Warming it up, or worrying about warming it up longer?

I decided for me the amount of fuel and the cost to warm up my car was inconsequential, whether I warmed it for 30 sec. or 15 min. There are easier and safer ways to cut 50 cents a week out of my budget than freezing my butt off, and risking the windows fogging up as I'm merging onto the interstate, as on my morning commute. Most of us throw away a couple bucks here and there, on a snack or coffee, without a second thought.
HotRod10
Champion Author Wyoming

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Message Posted: Mar 22, 2015 11:13:45 AM

nru, around here many people partially or even fully block the radiator with cardboard in the winter to help vehicles stay up to temp. Just have to watch the temp. gauge for a while after doing it to make sure you haven't blocked too much.
dontuknowOH
Champion Author Ohio

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Message Posted: Mar 22, 2015 11:00:18 AM

nru; I really think that at near 0 F temps you are doing a wise thing, to let you vehicle gain a jump on engine warming, before causing very cold air blasts to enter the engine compartment during travel speeds.

Artic air blasts definitely resist vehicles to gain proper operation temps. I can always tell by My cars suspension stiffness when temps drop into the single digits and below. One...three minutes make a big very noticeable difference.
poetdog73
Champion Author Toledo

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Message Posted: Mar 22, 2015 12:06:22 AM

only when its below 30!
hyeglenn
Champion Author Fresno

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Message Posted: Mar 21, 2015 4:07:42 PM

Only in winter months.
dontuknowOH
Champion Author Ohio

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Message Posted: Mar 21, 2015 11:48:09 AM

Keep a good recommended oil filter and proper weight/type lubricants in the vehicle's engine/drivetrain, have cabin filter renewed when necessary, driving away moderately should be fine for a warm-up, modern vehicle.
twt
Champion Author Virginia Beach

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Message Posted: Mar 21, 2015 10:20:01 AM

A waste, of time and fuel.
b899
Champion Author Connecticut

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Message Posted: Mar 21, 2015 8:53:55 AM

no
spam1111
Rookie Author Springfield

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Message Posted: Mar 20, 2015 9:50:57 AM

I am concerned about the idling factor I usually warm my car for less than 5 mins. Now i'm wondering if it was all wasted efforts.
dontuknowOH
Champion Author Ohio

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Message Posted: Mar 17, 2015 10:07:54 AM

I just remember that anytime the key is on and the engine is then running, that vehicle is also using fuel, and not running on air only.

Also note that to move away in drive mode, whatever, then the go pedal must be pressed for reliable motion. Motion that requires more rev energy, more fuel energy when that vehicle is in it's enrichment mode.

The older past term was a choked engine using more rich fuel to perform. Nasty by todays standards, with older vehicles. just remember that until your engine has reached normal operation temps, extra fuel will be compensating for the hurry travel attitudes at the go pedal even with a modern vehicle. Better than Decades ago technology! Still your choice counts. HAGD!
runner1256
Sophomore Author New Hampshire

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Message Posted: Mar 17, 2015 6:36:33 AM

I always figure my car is warm enough in the garage, so I get in it, sit for less than a minute, and drive away
b899
Champion Author Connecticut

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Message Posted: Mar 17, 2015 6:23:36 AM

no
nru
Champion Author Twin Cities

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Message Posted: Mar 16, 2015 4:22:22 PM

When the air temp is below 10F, I let my car warm up for a bit before I drive - the cold blast actually cuts my fuel economy a bit on my way home if I don't let it warm up some before leaving. I warms up quicker when idling than driving when it gets really cold (below 0)
drmiller0711
Sophomore Author Winston-Salem

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Message Posted: Mar 16, 2015 8:54:27 AM

Not that I am aware of
b899
Champion Author Connecticut

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Message Posted: Mar 16, 2015 7:17:20 AM

no
eyegotgas2
Champion Author British Columbia

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Message Posted: Mar 14, 2015 8:15:30 AM

I think most people just warm the car up so that its warm when they are ready to drive it, It has to use more gas because the vehicle is running.
atech54
Rookie Author Indianapolis

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Message Posted: Mar 13, 2015 2:42:47 PM

I would weather let the car warm up and waste a few dollars on gas, then to pay more for repair cost later.
HotRod10
Champion Author Wyoming

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Message Posted: Mar 13, 2015 11:29:23 AM

"A simple ,non-rocket science method, would use An accumulator installed on the engine to run parallel with the main oil pump."

A simpler method that gets you essentially the same result is installing an oil filter with an anti-drainback valve. They are available for most vehicles now (required for the warranty on some) for a couple bucks more than the cheapo ones.

Back to the subject - is it more economical to idle and drive the car after it warms up or just get in, start it and drive? The answer is there is a negligible difference in fuel used either way. From the information I gathered from other gas buddies and from an ecomodder page, a 15 minute warmup uses between .05 and .2 gallons of gas, depending primarily on the engine size, with a typical 4 or 6 cyl. car around .1 gal. Approximately half of that fuel loss is recouped in increased mileage in the first five minutes of driving a vehicle where the engine is already warm, instead of a starting off cold.

So, for most of us, the net result of warming the car is a difference of 1/20th of a gallon or about 12 cents. The comfort, convenience, and safety of driving a warm vehicle is easily worth it to me. There are other ways to save a few cents or a few tablespoons of gas that don't compromise safety or comfort.
b899
Champion Author Connecticut

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Message Posted: Mar 11, 2015 7:51:23 AM

no
GasMiser718
Champion Author Detroit

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Message Posted: Mar 10, 2015 5:37:29 PM

It doesn't matter, I am going to warm it up in the winter anyways.
redfish67
Champion Author Dallas

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Message Posted: Mar 10, 2015 11:40:38 AM

no
b899
Champion Author Connecticut

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Message Posted: Mar 10, 2015 9:21:21 AM

no
ShortyT2014
Sophomore Author Lexington

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Message Posted: Mar 9, 2015 5:12:20 PM

not me
Tucsonhomes
Champion Author Tucson

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Message Posted: Mar 9, 2015 3:42:42 PM

no
b899
Champion Author Connecticut

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Message Posted: Mar 9, 2015 9:01:22 AM

no
hoopitup2000
Champion Author Virginia

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Message Posted: Mar 6, 2015 7:18:34 AM

Not really.
b899
Champion Author Connecticut

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Message Posted: Mar 4, 2015 9:16:24 AM

no
dontuknowOH
Champion Author Ohio

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Message Posted: Mar 1, 2015 8:56:01 AM

Hemond ; If one really thinks about it, when the modern engine is cranked over during the start procedure. Then there is no or very little air entering the engine to allow much compression pressure to take place in the cylinders, hence offering a bearing load.

As long as the ECM doesn't allow ignition spark fire-up or EFI injecting fuel then there is NOT severe bearing load during cranking mode. The only modification that would be needed is preventing spark energy to be delayed until the oil pump reached proper pressure at all bearings.

My belief is oil pumps are positive displacement type pumps that can produce high pressures when activated, always stay primed, and except for the pressure relief valve as a bypass protector, they the pumps produce within 1.5 seconds oil pressure.

If not an electric/hydraulic switch could be fitted to kill spark fire/EFI delay until the bearings are initially protected/lube primed. Compression stroke loads aren't severe with no mass amounts of air allowed into the vacuum side of the engine, aIsi ....... Foot off the pedal when starting!
Hemond
Champion Author Providence

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Message Posted: Mar 1, 2015 8:01:22 AM

QUOTE:::::most factory oil pumps are mechanical, just bypass the mechanical oil pump with an electrical one. Turn the key, program a 2-3 sec delay to get the oil flowing, then start.::::


How do you tap into the oil flow? where is a point where you can access an oil line to rig up an auxiliary pump?. The pressure sending unit? Is there an easy exposed place to tap into the oil flow in car engines?
b899
Champion Author Connecticut

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Message Posted: Mar 1, 2015 6:17:14 AM

no
Shockjock1961
Champion Author Illinois

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Message Posted: Feb 28, 2015 10:42:08 PM

" There is no sound reason to have to warm up a car prior to driving away."

Sure there are, with safety being the prime reason...
nru
Champion Author Twin Cities

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Message Posted: Feb 28, 2015 8:41:45 PM

Below 10F I let mine drop off high idle before moving
drgeeforce
Veteran Author Los Angeles

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Message Posted: Feb 28, 2015 12:59:30 PM

@borsht, most factory oil pumps are mechanical, just bypass the mechanical oil pump with an electrical one. Turn the key, program a 2-3 sec delay to get the oil flowing, then start.
borsht
Champion Author Oakland

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Message Posted: Feb 28, 2015 12:11:53 PM

A simple ,non-rocket science method, would use An accumulator installed on the engine to run parallel with the main oil pump.
When the engine is running the accumulator charges with oil from the oil pump in the engine. When the engine is shut off a solenoid valve is closed trapping the oil, under pressure, in the accumulator. When starting the engine the next time all you do is turn the key to the on position a second or so before starting to release the oil to pre-lube the engine.

The only moving additional part would be the solenoid valve. Just fire the solenoid when the key is turned on.
In fact just fire it when the gasoline pump does it initial run when starting up to pre pressurize the fuel injectors.
borsht
Champion Author Oakland

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Message Posted: Feb 28, 2015 11:46:32 AM

The engine needs oil flow to all bearing surfaces before placing a load on the engine for max engine life. It's not the warm up per-se.
It would be good if the oil companies designed in a pre-start-up oil pump
to get the oil flowing before one starts his engine>

[Edited by: borsht at 2/28/2015 11:46:53 AM EST]
twt
Champion Author Virginia Beach

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Message Posted: Feb 28, 2015 11:21:27 AM

A waste of fuel.
carinthuist
Champion Author San Francisco

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Message Posted: Feb 28, 2015 10:51:04 AM

no
drgeeforce
Veteran Author Los Angeles

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Message Posted: Feb 27, 2015 6:07:36 PM

Dipstick oil heaters and magnetic oil pan heaters are cheaper options.
xtremecheap
Champion Author Arkansas

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Message Posted: Feb 27, 2015 5:36:23 PM

Cars are designed to drive, not idle.
blk911
Champion Author Colorado Springs

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Message Posted: Feb 27, 2015 4:11:28 PM

Big Waste!
MsPeachi747
Veteran Author Cleveland

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Message Posted: Feb 27, 2015 1:05:56 PM

Warming up the car so auto fluids get dispersed throughout auto is the best way to save auto engine and auto parts.
ChiefNolarama
All-Star Author Nebraska

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Message Posted: Feb 27, 2015 10:51:38 AM

Warm up the car for comfort - there is no other reason to do it.
b899
Champion Author Connecticut

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Message Posted: Feb 27, 2015 8:18:55 AM

no
jitsu
Rookie Author New York

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Message Posted: Feb 27, 2015 6:54:44 AM

I start the car and drive off. There is no sound reason to have to warm up a car prior to driving away. If one wants to have a warm vehicle to enter install a remote starter. Remember you are using gasoline if you allow vehicle to idle in driveway for the ten minutes or so it takes to warm up. It is each of our choices to make....
dontuknowOH
Champion Author Ohio

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Message Posted: Feb 27, 2015 6:42:07 AM

Yes I have some "WOSSEY" Days called older age, and mild so far, I'll blame it on the Weather! My vehicles have heaters, that actually work much better on modern vehicles.

The big BUT is they could be much better on quicker heat production time interval to the cabin areas/vents. Like 45 seconds for results... NICE !
Hemond
Champion Author Providence

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Message Posted: Feb 27, 2015 6:41:41 AM

In reality poorly said. Ignores the reason to warm up. Which is for comfort.
hoopitup2000
Champion Author Virginia

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Message Posted: Feb 27, 2015 6:13:43 AM

"repeat, mechanically there is zero need to warm the car..."

Well said & enough said . . . . . .
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