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Rob V
04-18-2005, 11:24 AM
While reading through the Online Manual I downloaded from the Owner Circle site, I found that it is not recommended to turn on the car and leave it running to warm it up. The manual recommends that you turn on the car then drive off at moderate speeds to warm up the engine.

That's all fine and good.....but what about those of us who live in cold weather areas where you have snow and ice built up and the temperature in the car is below freezing? Even if there isn't any snow or ice it's still pretty common to warm up the car before you drive off so that it's at least not blistering cold as you're driving. Will this really cause damage to the car?

By the way for those of you still waiting for your X3 on order (like myself) the Owners Circle web site finally posted the 2005 X3 manual. Not that it's much different from the 2004 but it's there if you need it.

pipo
04-18-2005, 12:38 PM
While reading through the Online Manual I downloaded from the Owner Circle site, I found that it is not recommended to turn on the car and leave it running to warm it up. The manual recommends that you turn on the car then drive off at moderate speeds to warm up the engine.

That's all fine and good.....but what about those of us who live in cold weather areas where you have snow and ice built up and the temperature in the car is below freezing? Even if there isn't any snow or ice it's still pretty common to warm up the car before you drive off so that it's at least not blistering cold as you're driving. Will this really cause damage to the car?

By the way for those of you still waiting for your X3 on order (like myself) the Owners Circle web site finally posted the 2005 X3 manual. Not that it's much different from the 2004 but it's there if you need it.

I don't believe it's an issue of causing damage to the vehicle by warming it up. Instead, I believe that the lubrication system in modern engines doesn't require the engine to be warmed up before driving on a cold day to prevent damage. BMW is probably just giving us a gas saving tip.

Rob V
04-18-2005, 08:07 PM
I suppose you're right. I just brought it up because the manual was pretty ademant about this. The direct quote is "Do not allow the engine to warm up while idling. Begin driving immediately at moderate engine speed." I just don't see a way around it in very cold weather.

pipo
04-18-2005, 09:07 PM
I suppose you're right. I just brought it up because the manual was pretty ademant about this. The direct quote is "Do not allow the engine to warm up while idling. Begin driving immediately at moderate engine speed." I just don't see a way around it in very cold weather.

I could be wrong, but this is probably a reflection of their Prussian heritage: a no nonsense, commanding attitude. They build great cars, but they don't bother themselves with such niceties as suggesting that there is no need to warm up the engine. Since it is not necessary, they don't even contemplate the notion that some people might want to warm up the car to make it more comfortable on cold days.

Maybe someone with more of an engineering background than me can shed some light on this?

B r i a n
04-19-2005, 06:01 AM
Simply put, if you leave the engine at idle to warm up it will be in a cold state longer.
The longer the engine is in a cold state the more wear occurs.
Most wear occurs in an engine when it is cold.
On the other side you do not want to bring the RPM above 3,000 or try to pull a heavy load when the engine it still cold.
In very, very cold weather it may make sence for the engine to idel a short time before putting any load on the engine
Hope this helps.
:) 2005 X3 3.0 :)

rrinker
04-19-2005, 08:33 AM
Harder to do in the X3 as it is Step, but in my 328 my usual on cold days was to start up, let it idle for about 30 seconds, and drive off. Not above 2K RPM until the temp needle started to move, and then not above 3K rpm until the temp was normal or close to it.
Too cold? Waiting for heat? That's what heated seats are for. :D

--Randy

Rob V
04-19-2005, 09:01 AM
Harder to do in the X3 as it is Step, but in my 328 my usual on cold days was to start up, let it idle for about 30 seconds, and drive off. Not above 2K RPM until the temp needle started to move, and then not above 3K rpm until the temp was normal or close to it.
Too cold? Waiting for heat? That's what heated seats are for. :D

--Randy

Sure that's what the heated seats and steering wheel are for but what good are they if there is a half inch of ice on the widshield and windows? :)

I guess I'll just go through my normal routine of turning on the car and windows defrosters and wait a couple of minutes unless someone can tell me that this will cause any damage. But from the responses so far it looks like it's not a huge deal.

dkl
04-19-2005, 01:56 PM
I think the main reason BMW wants you to bring up the engine temperature (as well as other moving parts) as quickly as possible by driving it is so that any moistures that may accumulate in the lubricant (engine oil, transmission oil, etc) would get evaporated as quickly as possible (idling won't warm this up as quick). Since moistures suspended in the lubricant will make it less effective, thus promotes more wears on the engine parts.

x3ronnie
04-19-2005, 04:21 PM
I live in a cold weather area and don't feel the need to warm up the X3. The heat comes on very quickly and the windows thaw right out. It's really quite nice.

philippek
04-19-2005, 04:36 PM
That's all fine and good.....but what about those of us who live in cold weather areas where you have snow and ice built up and the temperature in the car is below freezing?


Engine block heater? :dunno:

Rob V
04-19-2005, 05:15 PM
Engine block heater? :dunno:

HAHA! Thanks but I disn't mean North Dakota-type cold. It doesn't get that cold normally but especially at work the car is out in the elements the entire day and buid up a lot of snow and ice. But I guess from these posts it doesn't really take that long to warm up anyway. We'll see how it goes next winter.

rrinker
04-20-2005, 08:46 AM
Sure that's what the heated seats and steering wheel are for but what good are they if there is a half inch of ice on the widshield and windows? :)

I guess I'll just go through my normal routine of turning on the car and windows defrosters and wait a couple of minutes unless someone can tell me that this will cause any damage. But from the responses so far it looks like it's not a huge deal.

Guess that's why I have a garage at my house :D :D :D Car is cold in the winter, but no ice and snow on it. ;)

Woody
04-20-2005, 06:32 PM
I want to believe that it is emissions related (EPA). Cars pollute the most when they are cold. The sooner a car warms up the less emissions it puts out.

rrinker
04-21-2005, 02:08 PM
It's all related. Lower emissions for sure, but reducing condensation in the oil is also true. With today's tighter machining tolerances, there's a lot less 'slop' in the moving parts that causes excessive wear until the oil is fully pressurized. That doesn't mean you should start the engine and immediately floor it though.

--Randy

Rob V
04-21-2005, 02:43 PM
It's all related. Lower emissions for sure, but reducing condensation in the oil is also true. With today's tighter machining tolerances, there's a lot less 'slop' in the moving parts that causes excessive wear until the oil is fully pressurized. That doesn't mean you should start the engine and immediately floor it though.

--Randy

But does it mean that it truly isn't recommended to keep the car warming up for a couple of minutes?

pipo
04-21-2005, 03:59 PM
It's all related. Lower emissions for sure, but reducing condensation in the oil is also true. With today's tighter machining tolerances, there's a lot less 'slop' in the moving parts that causes excessive wear until the oil is fully pressurized. That doesn't mean you should start the engine and immediately floor it though.

--Randy

Also, the oil "pressurizes" almost instantaneously in today's engines, another factor that reduces the wear and tear that was inflicted on yesterday's engines by cold starts. My feeling is that idling the car to warm it up and/or moderate use of the throttle when driving off after a cold start are both acceptable and sensible approaches that should not cause any undue wear and tear. As you suggest, though, a full open throttle with a cold engine is not a good idea. My wife does it every day, but that's a different story.

M-PIRE
04-21-2005, 05:15 PM
Maybe it's just me, but couldn't you just scrape the ice then start the car when you are ready to roll? :dunno:

Rob V
04-21-2005, 07:05 PM
Maybe it's just me, but couldn't you just scrape the ice then start the car when you are ready to roll? :dunno:

Of course......but why when I can be in the house finishing getting ready. :p Look, it's not a huge deal but it's what I (and most people in this area) are used to and do pretty frequently. It's pretty much SOP during the colder winter months. I guess I'll just keep doing my normal routine. It doesn't sound like I'll be causing any real damage.

rrinker
04-21-2005, 09:42 PM
But does it mean that it truly isn't recommended to keep the car warming up for a couple of minutes?

I really doubt that warming up for a few minutes is goign to hurt anything. If every day you start teh engine and let it sit there idlign for 30 minutes or more - that's probably not too good. Long term idling, even with older less sophisticated engines, is generally grounds for putting you into the 'severe service' category. But starting up and letting it warm up for 5-10 minutes while you scrape the ice off isn't going to ruin your motor.