Oh yeah, the cold start season is here. Let the cold start rituals begin.
What's current best practice for warming up a vehicle?
- Thread starter OM617YOTA
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If it starts, I find that driving is the most effective way to warm it up. My neighborhood is 25 mph limit, so kinda implicates easy driving for the first few miles.
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You'd be surprised what percentage of car owners in this country have to bring the champagne out every time they are able to simply park within walking distance of where they live, and have seen things like garages, driveways, or dedicated parking spots with electric outlet access in sitcoms and movies only.
Let them not eat cake.
If your location is that densely populated, you probably don't need a car very often. I think his broader point is still valid.
The Subaru indicator is not about waiting till it goes off. It’s more about driving gently when blue, once off you can operate normally.
My wife’s commute for last 25 years is 3 mins off highway. She drives gently leaving work on stone cold motor and has it doing 75 mph within 3-4 mins with gentle acceleration. These turbo engines all working perfectly into the 200-300k range when we sold.
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Most such areas require the car moved once or twice per week if parked publicly. Even if you don't use it often, when you use it is one of those times you need it warmed up. Short trips to change parking spots etc.
In suburbia housings, there are whole regions where you have a spot or at least a dedicated parking, but no access to an outlet to plug a heater in.
What vintage is your Infiniti? Perhaps it may do it to mine but they're older stuff. That is nice Nissan has incorporated that into your ECU. Could certainly help w/trying to be easier on the transmission. Just got done watching an older Q45 YT video the other day.. I just need enough cash to buy a new 25' Q80 & I'll be set w/the family.
Hey, if we had a remote start I'd do the same. As of right now my wife is the "Remote Starter" but I've done my work.At home, we park in our garage so it's not that bad. At work, I'll start mine and let it warm up (the interior) for 5 minutes routinely. My wife remote starts her car, then has a ~10 minute walk. If she's paying attention to her phone app and it tells her it shut off after it's time limit, she'll restart it !
The only vehicle w/RS I've owned was when I had a stereo shop install one on my 98' Eldorado in 09'. It wasn't a great job done b/c It would randomly honk the horn after that work was done.
I didn't have a garage for my first 40 years. And I was starting my cars in -20F (and colder) weather. But I did have a block heater, and I used it every cold night.
In this area people fill their garage with stuff and park outside. And then scrape their windows on cold mornings. Makes no sense to me.
Being able to park in a garage is one of the biggest luxuries in the world.
I think warming-them-up it's just another left-over myth - like batteries go dead if sitting on concrete and laying a refrigerator on it's side is certain death for it. Both of which were true at one time but haven't been since before WW2. <g> I guess we could throw in "always run the engine to heat the oil before draining it" too. <g>
Don't forget that oils were once all single grade, non-detergent, and fairly crudely concocted. As were the engines for that matter. So warming the moving parts and the oil was somewhat important at one time. Now I do still drive a light foot until I see the temp gauge move - but it more old habit than necessity so far as my actual experience goes. I have three trucks all pushing or over 250K now and, except for the rare VERY cold days where the seats are too cold to tolerate, none have ever been 'warmed up' before driving.
Oh wait - I did shove a junk yard motor in the 2005 GMC 4.3 at about 175K - broke a valve spring, I guess from running it 100 all day and night. <g> So maybe I can't use that as an example. But the 2000 GMC 5.7 and the Tacoma 2.7 are still in the running. <g>
I have used Mobil 1 in everything almost since the Mobil Oil Research Lab boys were all crowing about their test stand results - so maybe that's a factor too.
Don't forget that oils were once all single grade, non-detergent, and fairly crudely concocted. As were the engines for that matter. So warming the moving parts and the oil was somewhat important at one time. Now I do still drive a light foot until I see the temp gauge move - but it more old habit than necessity so far as my actual experience goes. I have three trucks all pushing or over 250K now and, except for the rare VERY cold days where the seats are too cold to tolerate, none have ever been 'warmed up' before driving.
Oh wait - I did shove a junk yard motor in the 2005 GMC 4.3 at about 175K - broke a valve spring, I guess from running it 100 all day and night. <g> So maybe I can't use that as an example. But the 2000 GMC 5.7 and the Tacoma 2.7 are still in the running. <g>
I have used Mobil 1 in everything almost since the Mobil Oil Research Lab boys were all crowing about their test stand results - so maybe that's a factor too.
I find the best way to start a vehicle with a manual transmission is with the clutch depressed. When I release the clutch a few seconds later (transmission in neutral) the engine slows for a few seconds.
I've worked in places where vehicles were left running all day. That was at anything below -40. They were only stopped for a few minutes to change the oil every few weeks. If they were stopped for any length of time they might not start. In that case they had to be dragged into a building to warm up, which was a big nuisance.
I'll weigh in on this topic as a North Dakota native and engine guy.
The "best" practice is to start the engine. Do you have oil pressure? There is a rough ratio of time to build oil pressure (from cranking) to time where oil has reached all the rest of the engine. It's around 5:1 on the upper end. So if it takes one second to have oil pressure in the main oil rifles, you'll have oil at the top end and everything else within 5 seconds. This is true even of the massive 95L V16 QSK95 Cummins makes, which has oil pressure at the mains in under 2 seconds even on a cold (near freezing) start .
Which means that after 5 seconds or so, the engine is not receiving any more oil or any better lubrication. There's no advantage to further idling in terms of engine wear reduction because you're already in full elastohydrodynamic lubrication (let's call it EHDL, please).
IN bitter cold temps with marginally suitable oils, it might take 4 or 5 seconds to have oil pressure at the main rifles. Which means it could take as much as 25 second or so to get oil to the top end and all the rest of the engine.
So, regardless of ambient temperatures, idling more than 30 seconds is not beneficial if you chose an oil that is remotely appropriate for your local climate.
Engines make more heat at higher rpm and with some load on them. That's pretty obvious. It's also obvious that your engine will warm up faster then if it has some load on it (i.e. driving) instead of idling.
Elevated RPM in a cold engine is your friend, within reason. Keeping it around 2000-2500rpm assures good oil pump output, good coolant flow (and heat distribution) and it also reduces wear at the top ring reversal.
So what is "ideal" is cold start, idle no more than 30 seconds, then take off driving gently (mild throttle) but allowing the engine to rev to keep engine torque low.
Now, if you idle longer to scrape window or whatever, you're not really hurting the engine by much of anything measurable. It will shorten oil life and that's about it.
Use a really good high viscosity index oil with a nice dose of Moly, a pour point at least 20 degrees lower than your coldest start, and a cranking viscosity under 6000cP at your worst case start. Then get on with life.
The "best" practice is to start the engine. Do you have oil pressure? There is a rough ratio of time to build oil pressure (from cranking) to time where oil has reached all the rest of the engine. It's around 5:1 on the upper end. So if it takes one second to have oil pressure in the main oil rifles, you'll have oil at the top end and everything else within 5 seconds. This is true even of the massive 95L V16 QSK95 Cummins makes, which has oil pressure at the mains in under 2 seconds even on a cold (near freezing) start .
Which means that after 5 seconds or so, the engine is not receiving any more oil or any better lubrication. There's no advantage to further idling in terms of engine wear reduction because you're already in full elastohydrodynamic lubrication (let's call it EHDL, please).
IN bitter cold temps with marginally suitable oils, it might take 4 or 5 seconds to have oil pressure at the main rifles. Which means it could take as much as 25 second or so to get oil to the top end and all the rest of the engine.
So, regardless of ambient temperatures, idling more than 30 seconds is not beneficial if you chose an oil that is remotely appropriate for your local climate.
Engines make more heat at higher rpm and with some load on them. That's pretty obvious. It's also obvious that your engine will warm up faster then if it has some load on it (i.e. driving) instead of idling.
Elevated RPM in a cold engine is your friend, within reason. Keeping it around 2000-2500rpm assures good oil pump output, good coolant flow (and heat distribution) and it also reduces wear at the top ring reversal.
So what is "ideal" is cold start, idle no more than 30 seconds, then take off driving gently (mild throttle) but allowing the engine to rev to keep engine torque low.
Now, if you idle longer to scrape window or whatever, you're not really hurting the engine by much of anything measurable. It will shorten oil life and that's about it.
Use a really good high viscosity index oil with a nice dose of Moly, a pour point at least 20 degrees lower than your coldest start, and a cranking viscosity under 6000cP at your worst case start. Then get on with life.
That's a perfectly valid approach-- for Arizona.
I used the same approach when I lived in Western Washington. It gets surprisingly cold in the winter here. Our home is at 3,600 feet.
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I live in the South East ( Carolina ) so I have cool mornings, but only a few COLD mornings.
On a Cold morning I have ALWAYS walked outside and started my car truck ( long before remote start ) walk back inside and let thing warm up a good 5 min but those days are seldom ( a few times a year I guess ).
However, I own Harley motorcycles and the first start of the day even in Summer I start the bike get off and then put my helmet on, glasses etc so my air cooled Harley always gets a warm up and then I drive off slow and keep it slow a good 3-5 + miles down the road!
I also give everything a quick cool down time out of habit as I have owned cars and trucks with a Turbo so its normal to not be so quick to turn things off and let the turbo cool down1-2 min or longer if pulling a trailer.
I in general simply don't get in a rush with anything but I am the kinda person that is NEVER late to anything so I seldom find myself in a situation that I don't have the time to at least get the oil flowing and again, I take off slow and keep the RPMs down the 1st few miles in the morning and then again, let things cool down and the turbo stop spinning once back home.
On a Cold morning I have ALWAYS walked outside and started my car truck ( long before remote start ) walk back inside and let thing warm up a good 5 min but those days are seldom ( a few times a year I guess ).
However, I own Harley motorcycles and the first start of the day even in Summer I start the bike get off and then put my helmet on, glasses etc so my air cooled Harley always gets a warm up and then I drive off slow and keep it slow a good 3-5 + miles down the road!
I also give everything a quick cool down time out of habit as I have owned cars and trucks with a Turbo so its normal to not be so quick to turn things off and let the turbo cool down1-2 min or longer if pulling a trailer.
I in general simply don't get in a rush with anything but I am the kinda person that is NEVER late to anything so I seldom find myself in a situation that I don't have the time to at least get the oil flowing and again, I take off slow and keep the RPMs down the 1st few miles in the morning and then again, let things cool down and the turbo stop spinning once back home.
Yes, coincidence. I suspect it's actually 50C (122F) as almost nobody does engineering in English units-certainly not Subaru. You'll find round numbers in SI are quite common. But not in any natural process.
Nature and physics have no way of knowing what units of measure you are choosing to use, and it's almost impossible for natural processes to occur on round numbers of a scale. The celsius scale has perfect round numbers for the freezing and boiling points of water because it was defined by those points. Other than that, good luck finding anything in nature that happens exactly on even multiples of 10C or 10F.
Cummins fuel system literature publishes a maximum inlet temperature of 70C. That point? It's as arbitrary as the width of a railroad track being based on the spacing of a two-horse team. We test and validate the pump at temps up to 70C, so it's the limit because that's what we chose to design for and develop to. Or rather what Bosch did, and created essentially an industry norm when everyone followed Bosch. (interestingly enough, it's the same reason the automotive relays have the numbering scheme they have-- blame Bosch and their penchant for innovation). But look at the spec sheet for a high pressure common rail diesel pump from Bosch, Cummins XPI, Denso, or even Liebherr or Woodward-- all use 70C. And all are just following the arbitrary level Bosch set as the first to do it.
The point here is that this 50C "cold" engine light is also arbitrary. There's no reason to consider 50C "warm" but 45C as "cold" other than force of will. There's no major change of oil viscosity or engine clearances that would distinguish them.
In over 40 years driving manual transmission, I can't recall any of mine that didn't have a clutch interlock and it had to be pushed down.
7.3L gas engine in my truck.
This time of year, morning temps around 0 to -10C (32-14F) I'll let it idle 10-15min before leaving.
As we get into colder temps like -15 to -40C (5 to -40F) I will let it idle the full 30min max of the remote start.
My truck idles hours most days so I don't concern myself with idle time.
This time of year, morning temps around 0 to -10C (32-14F) I'll let it idle 10-15min before leaving.
As we get into colder temps like -15 to -40C (5 to -40F) I will let it idle the full 30min max of the remote start.
My truck idles hours most days so I don't concern myself with idle time.
I worry a bit more about the transmission, than the engine for cold starts, as our driveway is about a 10% grade for a couple hundred yards.
My wife doesn't though, and so far the Outback just takes the 25-35% throttle run after 20 seconds of idling in some pretty cold weather, -15C, it just revs to 2600 rpm with the torque converter unlocked, to make some heat as it grumbles up the hill. It will keep the TC unlocked for a mile or 2, if your asking for maximum heat, but I think that's fairly common now? It is odd to turn down the heat a notch and have TC lockup, but I guess the engineers had their reasons.
My wife doesn't though, and so far the Outback just takes the 25-35% throttle run after 20 seconds of idling in some pretty cold weather, -15C, it just revs to 2600 rpm with the torque converter unlocked, to make some heat as it grumbles up the hill. It will keep the TC unlocked for a mile or 2, if your asking for maximum heat, but I think that's fairly common now? It is odd to turn down the heat a notch and have TC lockup, but I guess the engineers had their reasons.
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