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Under Worked and Over Paid
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warming up your car? How long do you warm up for and what benefit does it provide. I always thought it just gets the oil around so about 20-30 seconds is ok. Who does and how long do you warm up your car? :dunno:
 

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i don't warm up...i just crank and ride the F*** out, although i do keep the rpm's under 3000 for the first several miles until optimal operating temp is achieved. Hope this helps.:thumbup:
 

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The point of letting a car warm up is to let the temperature of the engine metals reach their operating temperature, and thus expand (or contract) relatively slowly. It is better than staring your car and taking off to redline.

There is no magical formula and things are going to expand reguardless, but it is better to let it idle for a minute and then drive up to 3000 RPM for a good 5 minutes before taking off to redline.

There are, as always, 18,000,000 parameters of an engine that make it a good idea, but it will not kill an engine instantly if you do not let it warm up. After 100,000 miles though, it could (read could) be a cause of worn out rings and pistons.
 

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m32 said:
I could've sworn on my M manual that it said do not let it warm-up. Just start it up and drive
It does say in the manual to start the car and drive immediately at a moderate pace. I ususally let it sit a bit until the rpm drops to near idle, which takes about a minute or less.
 

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i warm-up until it's out of the blue range.
 

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:blah: I'll trust the people who made the engine thanks... :rtfm:
 

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yeah, i used to warm my engine up too, but after reading the manual, they said just GET GOING, but keep the RPMs at a moderate level. you also have to remember that your tranny needs to warm too. so redlining and powershifting when cold can do lots of damage
 

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I always warm up at least 3-5 minutes on a stone cold engine.The reason the manual says start up and drive away is
so that BMW(and most other manufacturers) want to be seen by regulators to be ecologically cooperative in saving gas and causing less pollution-it's pc bs. You should always warm up a stone cold engine so that metals are expanded uniformly before putting them under the stress of driving. Don't the M cars have markings on their tachs that indicate limits as to how much/little you should rev-they disappear when you reach (warmed up) proper operating temperature. This goes for all engines altho you can do more damage quicker to a high strung M motor if you rev/load it before it's ready. BMW is just thinking of minimizing warranty liabilities with the M motors and in that case decided to screw the pc bs. Would you like to take off in an airliner whose engines aren't up to temp? do you think they
put stone cold engines on race starting grids? at the drags where
some engines even have to be rebuilt between runs do they race them from cold? A little common sense here, and a little reading between the lines please.
Start your engine from cold and shut down after say 30 secs. then
check your oil, smell the gas? It's slipping by the piston rings because they haven't expanded to proper heat generated tightness. When you start up from cold and put load on your engine quickly you're pumping more gas into your oil which is thinned out and less able to provide proper lubrication until engine is up to temp and the oil is at optimum viscosity to provide protection-engine heat also helps to burn off the gas in your lubricating oil especially on longer trips. Short trip, stop and go driving is the worst for your engine because your oil is almost always diluted and never gets a chance to be burned off.
 

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Liscia said:
I always warm up at least 3-5 minutes on a stone cold engine.The reason the manual says start up and drive away is
so that BMW(and most other manufacturers) want to be seen by regulators to be ecologically cooperative in saving gas and causing less pollution-it's pc bs. You should always warm up a stone cold engine so that metals are expanded uniformly before putting them under the stress of driving. Don't the M cars have markings on their tachs that indicate limits as to how much/little you should rev-they disappear when you reach (warmed up) proper operating temperature. This goes for all engines altho you can do more damage quicker to a high strung M motor if you rev/load it before it's ready. BMW is just thinking of minimizing warranty liabilities with the M motors and in that case decided to screw the pc bs. Would you like to take off in an airliner whose engines aren't up to temp? do you think they
put stone cold engines on race starting grids? at the drags where
some engines even have to be rebuilt between runs do they race them from cold? A little common sense here, and a little reading between the lines please.
Start your engine from cold and shut down after say 30 secs. then
check your oil, smell the gas? It's slipping by the piston rings because they haven't expanded to proper heat generated tightness. When you start up from cold and put load on your engine quickly you're pumping more gas into your oil which is thinned out and less able to provide proper lubrication until engine is up to temp and the oil is at optimum viscosity to provide protection-engine heat also helps to burn off the gas in your lubricating oil especially on longer trips. Short trip, stop and go driving is the worst for your engine because your oil is almost always diluted and never gets a chance to be burned off.
Wow... I didn't know about that whole PC-pollution thing. Thanks
 

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Liscia said:
I always warm up at least 3-5 minutes on a stone cold engine.The reason the manual says start up and drive away is
so that BMW(and most other manufacturers) want to be seen by regulators to be ecologically cooperative in saving gas and causing less pollution-it's pc bs. You should always warm up a stone cold engine so that metals are expanded uniformly before putting them under the stress of driving. Don't the M cars have markings on their tachs that indicate limits as to how much/little you should rev-they disappear when you reach (warmed up) proper operating temperature. This goes for all engines altho you can do more damage quicker to a high strung M motor if you rev/load it before it's ready. BMW is just thinking of minimizing warranty liabilities with the M motors and in that case decided to screw the pc bs . . . blah blah blah
All that stuff about being ecologically cooperative is a bunch of caca. The point is that driving with a warm engine and a cold transmission is likely to be bad, so it's better to gently drive the car until it's up to operating temp. In contrast to what you wrote, BMW says that you should NOT warm up the M3 before driving. You're supposed to just go.

From the 2004 manual: "Do not allow the engine to warm up by leaving it running while the vehicle remains stationary. Instead, drive off immediately at a moderate engine speed."
 

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Justin said:
:blah: I'll trust the people who made the engine thanks... :rtfm:
Come on bro. Use some common sense.

BTW...your owner manual also said change your oil ever 15,000 or 30,000 miles (can't remember which).

All these shi**tz about not warming up or changing your oil after a billion miles are all MARKETING campaign to make BMW sound superior

P.S I see that you have a brand new bimmer. Most people on this board are lifetime bimmer euthastists. Therefore, this make them a subject expert. Listen to their advice rather than listening to some owner manual that was produce for the "Average" dumb driver that doesn't know anything about car. A case in point is, have you seen the instructions on the manual? It is so simple and basic that a 5th grader can read it and understand it.

Charlie6 out!
 

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Good advice ADA, learn from those who know as I have. For people's info I have an '84 BMW 528e with over 250K on the odo
and one autotrans overhaul @ 160K-I think I've done some things right over the years? My son is whipping it these days.
 

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ADA said:


Come on bro. Use some common sense.

BTW...your owner manual also said change your oil ever 15,000 or 30,000 miles (can't remember which).

All these shi**tz about not warming up or changing your oil after a billion miles are all MARKETING campaign to make BMW sound superior

P.S I see that you have a brand new bimmer. Most people on this board are lifetime bimmer euthastists. Therefore, this make them a subject expert. Listen to their advice rather than listening to some owner manual that was produce for the "Average" dumb driver that doesn't know anything about car. A case in point is, have you seen the instructions on the manual? It is so simple and basic that a 5th grader can read it and understand it.

Charlie6 out!
If you read my signature you'd notice that I had a 2000 323i as well, so I've been driving bmws for 4 years now, not exactly a lifetime, but none the less I'm not a "new owner".

As far as it being a marketing campaign... When was the last time you saw a BMW commercial or advertisement that said "BMW, You don't have to warm up our engines!", or "BMW, you only have to change your oil every 15k miles!". You might want to take a marketing class or two before you tell me to use common sence. :thumbdwn:
 

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Just letting your car warmup at idle only warms up the engine and not the tranny and all other mechanical components.

If you start driving at a moderate pace as soon as you start your car, the car and every mechanical components will get to the optimal temperature as a whole risking less damage due to different thermic expansion...
 

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There I was, Sicily, 1918..
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OK, once again ;)

You do not have to warm up your engine by idling it. New engines (anything with fuel injectors) do not need it. It wastes gasoline. It warms up only the engine, leaving everything else cold (tranny, power steering, etc.) and in need of normal warming.

The main reason you used to have to warm up a car was because the carburetor need to be at a more 'normal' temp or else it would not deliver fuel properly and it would cause a stall; we do not have carbs. The fuel delivery system's also different, with a rear pump that delivers 90psi to the forward pump, which tones it down to about 30psi -- at that pressure, there's no way in hell those injectors aren't delivering fuel. We have a computer that controls the injectors to deliver the proper amount of fuel at the proper time -- these do not need to be warm to operate; the computer also adjusts the RPMs (you'll notice they're higher when the engine's really cold) much in the same way you used to choke a car with a carb (except it's automatically done and is more efficient).

Airplane engines (turbines) are completely different things, comparing them to your car is like comparing the plane's tires to yours -- yeah, they're both black and rubber, and that's about all they have in common. Race car engines are warmed (along with the rest of the car, I might add) in the pre-race warmup (they do a final lap right before it begins (Formula 1)), so they're driven 'cold' and easy for a little bit until they reach optimal temps., and then they're pushed. They also don't race them cold because pushing a cold engine is bad (that's something we all agree on). But you're not pulling out of your garage at 15,000rpm (or, considering our cars, about 6-7000)... I hope ;) Also, if you'll notice, those cars are never idle for long, as they do not receive proper cooling if they're not moving (much like ours, although to a much greater extent).

Incidentally, this is all coming from my dad, who's been a car mechanic (specializing in Mercedes, BMW, Peugot, and Fiat) for more than 40 years. Funny enough, he and I had this very same discussion yesterday about it.

I'm not flaming anyone -- take this from someone that wants everyone's ride to last 'em forever :)
 

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Sicily1918 said:
OK, once again ;)

You do not have to warm up your engine by idling it. New engines (anything with fuel injectors) do not need it. It wastes gasoline. It warms up only the engine, leaving everything else cold (tranny, power steering, etc.) and in need of normal warming.
Yes. Sicily and brew are right. Do what the manual tells you. That is what it is for.
 

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The REAL reason

Yes, fuel injection doesn't require the warmup of carburetors. Yes, idling wastes gas. Yes, it adds pollution. But no one expanded on the reason it adds pollution. The catalytic converters must be hot to work. THIS is the REAL reason the manual says to not warm it up. If you "warm" your engine up at idle for 2-3 minutes, you ARE polluting (and a lot more than you think), because the converter cannot get hot at idle. Try to start your car up and only idle it for 2-3 minutes and then try to get it to pass an emissions inspection. It won't. It won't hurt it to warm it up, but it WILL pollute. In non-extreme weather, I start my car, put in gear after about 5-10 seconds and don't drive like a maniac for a few minutes.

Don't get me wrong, I'm no tree hugger. I don't even care if you have catalytic converters. I just thought I'd explain it.

I also believe the billion-mile oil change is slightly off. They obvioulsy do this because they have free oil changes for first 36-48K mi. If they charged for all early maintenance, you can be sure the manual would say change the oil every 7500 mi or less.

ICBW, but I'm probably not.

Bill
 

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just warm it up for a minute or so before driving off.......


common sense here..........the manual also says no changing oil guys till how many miles are passed .........thats what i thought
 

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m32 said:
I could've sworn on my M manual that it said do not let it warm-up. Just start it up and drive
Don't you "M" cars have to wait for the tach leds to disappear before you start moving??

I just wait for my idle to drop, and drive off. Otherwise the car rides rough for a while and there is no need for that.

It's also tougher to get the car in gear if I just get in and go.
 
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