Warm up: how gentle?

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I'm fairly close to the freeway both at home and at work. On the way into work I go probably 1.25 miles before hitting the freeway and on the way home, only about .5-.75 miles. If I play my cards right and it's not too cold I can usually have the temperature gauge up to its normal position by the time I get on, but I don't know how close to actual operating temperature it is (damped gauge and my girlfriend stole my scangauge!).

Well, I like to have a little fun when possible and even aside from that, if I shift my 1.8L 4 banger at 2500 RPM I'm just not accelerating all that quickly. Even so, I always feel like I should be as easy as reasonable on the engine before it's warmed up. I don't like to drive it too hard until after driving for more than 15 minutes or so, and I don't do that very often. On the other side, I've driven with some co-workers who think nothing of flooring it onto the onramp a block away from the office, their ATs shifting near redline.

Out of curiosity, just how gently do other members here treat their cars during the warm-up period? Do your habits differ between smaller and bigger engines? I expect us BITOGers are all a little more ... "conscientious" about this than the average person, but how much difference does it really make?
 
If I'm driving a gasser, I pretty much start driving it normal as soon as the temp gauge moves a little. That indicates the thermostst is opening up and therefore the engine is warmed up. My truck pretty much the same but it takes much longer for the needle to move. On a gasser you don't really have much to worry about. There isn't much compression and it's naturally aspirated so you won't hurt anything by driving it hard, even when cold. But letting it warm up a little is always a good idea. The transmission also warms up fairly quick once put in drive.
 
On a cold start, I idle it for about 30 seconds, sometimes a little more, and then move away. I don't exceed half throttle or 2500 rpm until the engine is at operating temp; in winter, I keep it under one-third throttle and 2000 rpm until the temp gauge starts moving (much to the dismay of anyone who happens to be behind me at traffic lights).
 
When I warm up my truck, I idle it until the coolant temp reaches 40-50C or about 2 minutes. When I leave to go into town, I gently drive it keeping it under 2000RPM's to get off my street and onto the highway with moderate to heavy traffic and 2 stoplights along the way. It's about 3/4 miles until the freeway onramp. By then the temp guage will be about 70-80C. I stay on the right lane on the freeway driving 45-50 miles per hour. Until it reaches operating temp (86C), I switch lanes and follow the flow of traffic.
 
From the time I start my engine to the time I get to one of the freeways we frequent it takes about 4-5 minutes. By that time the temp gauge is usually in the normal zone, depending on which vehicle I'm in. The acceleration ramp is pretty long so pounding the gas pedal is rare. I gradually accelerate to highway speed 55-60 mph, w/o forcing a downshift. Doubt I'm doing the engine any harm at all. In well over 30 years of driving we've always lived no more than 5 minutes from any freeway, and nothing has self destructed yet.
 
I usually start driving right away. I try to be gentle on the gas pedal and not exceed 3k rpm until the coolant temp gauge is in its normal operating position (12 o'clock in my case). Then, I still take it rather easy for another 5 minutes or so and do not go past 3.5k rpm. After that it's open season...

But try not to shift too early to avoid the risk of lugging in the following gear, especially on a small engine with not a whole lot of torque down low. I would imagine lugging would be more harmful than running slightly higher rpms.
 
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There have been some occasions where after about 5-10 minutes run time after a cold start I had to nail it to merge into traffic. Sometimes it can't be avoided, but that is always a rare event.
 
I start,wait 1 min,drive slowly(.25 mile dirt road), ease out, drive reasonably for couple miles and then normal.

My wife

start,before key springs 0.00000000000001" back to run,shift to reverse while pushing accelerator pedal half way,brake while simutaniously shifting to D,catching the acc pedal with the heel of her foot as to gas engine just as her toe flips off the brake pedal,then proceeds to drive with no regard to engine rpm or any other factor. Try doing that in under a third of a second,she is a PRO!
 
Bambam,

You should get your wife a Porsche, the key is on the left hand side of the column so she can get it into gear that much faster!

I don't believe in waiting to move the car until it's warmed up. Maybe 10~15 seconds while I get buckled up, mirrors... etc. Then take it easy until the temp needle starts moving, about a mile or so.

When it's below 0, though, our Accord's manual transmission and radio really don't like it, so that car gets it a bit easier until it's full operating temp, probably five miles.
 
The problem is operating temp on a water temp gauge and the operating temp of the oil are two different things. In cold weather the water temp will reach its normal range in a short period of time, 5 minutes or less depending on engine design, and ambient temps. Where the oil will take 15-20 minutes, or longer. Hammering the gas before the oil reaches OT is not good for an engine, or at least that is what reading tons of threads lead me to believe. I'm glad my car beating days are over.
 
I remember back in the 1970s a guy who on cold winter days would get in his car, start it, and run it at what sounded like 3000 plus rpm for a couple minutes, then take off. Always wondered how his oil consumption was.
 
I used to live right by the freeway, and would drive less than 1/2 a mile before flogging the heck out of my old car to get onto the highway and the across to the first left exit less than maybe 1/16th of a mile past my exit. Maybe flogging the heck out of it wasn't always necessary, but I basically gave it at least one redline shift a day, minutes after starting, and when I sold it with 194K miles it didn't burn oil and ran fine.

The new car has much more power, so I can drive around without exceeding 2K RPM all day, but I still like taking it up to 6,000 every now and then. I do keep it down low until it's warmed up though.
 
I let my car run for a minute or so, OR I leave it run while I scrape off ice & snow. So sometimes it is well warmed up, sometimes not!

I live off a fairly busy road, so when you get an opportunity to go, you take it! So yeah, I've revved my engine to near redline quite a few times before the temp gauge is even moving. The engine is very, very noisy on those mornings!
 
Originally Posted By: John K
"my girlfriend stole my scangauge!"

Sounds like a story right there! A girl I's like to meet....



Well I suppose I could just take it back out of her car, but I'm just waiting until KiwiMPG comes out so I can get her one of those, since she only cares about the mpg reading.

Sounds like there's a spectrum, but mostly biased toward taking it easy (as expected). I try to shift at 3k or below until I've been driving for 10 mins or so generally, but occasionally I'll have to go up to 4 or 4.5k on an onramp (we have some fun, short, curved onramps with bad visibility until you're already on them). The other problem for me is I've got a 3 mile 7% grade on my way home within 5 miles or so of the freeway onramp. That's probably plenty of time for it to be warmed up, but either way the engine's hitting 3.5-4k RPM to climb that every night.

I think my GF is still having fun switching back to MT after driving an AT car for a few years, because whenever I drive with her she seems to shift at 3.5k or so right out of the driveway. I don't like to say anything about it, I'm thinking of it as a case study :)
 
Originally Posted By: addyguy

I live off a fairly busy road, so when you get an opportunity to go, you take it! So yeah, I've revved my engine to near redline quite a few times before the temp gauge is even moving. The engine is very, very noisy on those mornings!



Do you feel like this is doing any damage? (Subjective question, I know). Have you seen any evidence in UOA, or does this not happen enough to be a trend?
 
Good question. I've read tons of things about engines not being fully protected until oil reaches operating temps. Cyls being oval instead of round until they heat up, various studies, etc. I find it hard to believe that a car has to be driven for close to 20 minutes before it's "fully protected."
 
Originally Posted By: Bambam
I start,wait 1 min,drive slowly(.25 mile dirt road), ease out, drive reasonably for couple miles and then normal.

My wife

start,before key springs 0.00000000000001" back to run,shift to reverse while pushing accelerator pedal half way,brake while simutaniously shifting to D,catching the acc pedal with the heel of her foot as to gas engine just as her toe flips off the brake pedal,then proceeds to drive with no regard to engine rpm or any other factor. Try doing that in under a third of a second,she is a PRO!

That sounds about like what my wife does too... I suspect both of my cars see 4000rpm+ if she's running a bit late in the first 100 yards.
My Dad (mech engineer) actually is one of the least concerned people I know about engine warm up. They live just off a 2 lane hwy so within 30-60 seconds of start up their cars are doing 60mph. He figures its a reasonable design criteria for the engine not to be damaged while operating below ideal temperatures... The only car that might of complained about this treatment was the 89 3.0L dodge caravan, it blew a headgasket at 100,000 miles but that wasn't uncommon either with that engine.
Ian
 
Originally Posted By: IndyIan

They live just off a 2 lane hwy so within 30-60 seconds of start up their cars are doing 60mph.


That doesn't seem to me like it'd be a big deal in itself. Seems like the issue is more how the car gets to 60.
 
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