Engine Warm-up time

This is my first bimmer and I'm not too familiar with it. My previous Hondas and Toyotas usually took a mile or so to reach normal engine operating temp. or the needle said so anyway. The 335i on the other hand takes at least 3 miles or something for the needle budge any at all. Is this true with your bimmers too? Caveat: I have not changed my route to work.

Your previous Hondas and Toyotas, and most non-performance cars, have a coolant temperature gauge. This warms up significantly faster than the motor oil temperature, which is what is displayed in your 335i.

The manual for my X3 says specifically not to idle to let the motor warm up. What's the reasoning?

Idling is not the most efficient way to warm up the engine. Nor is it environment-friendly. The best way is to get going applying light load, i.e. no flooring until the engine reaches its nominal temperature.

The above posts are true, but since the OP states it takes 3mi for the oil temp to budge, we can assume that he/she is driving said vehicle.

I suggest giving the motor 10-15secs on a cold start to settle down, but I would not exceed 40s of just "sitting" because it puts a load on the catalytic converter and is otherwise harmful.

Originally Posted by AzNMpower32

The above posts are true, but since the OP states it takes 3mi for the oil temp to budge, we can assume that he/she is driving said vehicle.

I suggest giving the motor 10-15secs on a cold start to settle down, but I would not exceed 40s of just "sitting" because it puts a load on the catalytic converter and is otherwise harmful.

Would that be for all vehicles?

I let my e46 get to just above the blue in the temp gauge, which is usually within a minute of starting.

the motor oil temperature, which is what is displayed in your 335i.[/QUOTE]

Thank you for clarifying that for me. Didn't even consider that. So, does yours take that long to get to 200?

The warm up time will depend on ambient temperature. When it is cold out it will take longer. It will also depend on how long it has been since youve driven your car. I believe that BMW states that you should not apply full throttle until at least 170F(?) or so. Coolant temp is not a good indicator of engine warmup, so I doubt your hondas were really warmed up. the 335i has a oil temp gage and this is the safe way to interpret warmup. I am a little more conservative and will not redline my car until 200F is reached.

Here is my protocol: Start the car and let the engine run with the car parked until the engine idle drops down to the 800 rpm territory. Then drive slowly for about 1 - 2 miles. After the 1 - 2 mile point, normal driving. The initial high revs are programmed in to get the catalyst up to operating temperature as quickly as practical; so I let the catalyst get happy and then driving slowly for the 1 - 2 miles gets the rest of the engine 'warmed up'.

I have heard of engine heaters that can plug into your garage outlets. Do they make one for this car?

Originally Posted by desertdriver

the warm up time will depend on ambient temperature. When it is cold out it will take longer. It will also depend on how long it has been since youve driven your car. I believe that bmw states that you should not apply full throttle until at least 170f(?) or so. Coolant temp is not a good indicator of engine warmup, so i doubt your hondas were really warmed up. The 335i has a oil temp gage and this is the safe way to interpret warmup. I am a little more conservative and will not redline my car until 200f is reached.

+1

Originally Posted by TheCritic

The manual for my X3 says specifically not to idle to let the motor warm up. What's the reasoning?

I would like to see the exact wording in the manual.

Originally Posted by jxr209

I have heard of engine heaters that can plug into your garage outlets. Do they make one for this car?

There are block heaters and oil heaters and blanket heaters to put your battery on. They are generic. They are generally 110V.

For the block you knock out a water jacket plug and insert a heating coil into the water jacket. Oil heaters are a straight heating element and go in via the dip stick tube.

There are many kinds. I used two in a car I had when I lived in Alaska. They worked great.

Originally Posted by AzNMpower32

This warms up significantly faster than the motor oil temperature, which is what is displayed in your 335i.

Oil temp really? Are you sure? Its strange that a mfgr would show oil temperature and at the same time not show water temp. Unless it is related to the turbos

Originally Posted by franka

Oil temp really? Are you sure? Its strange that a mfgr would show oil temperature and at the same time not show water temp. Unless it is related to the turbos

"Unconventional" is a much more friendly word than "strange." These are BMWs we are talking about here.

OK unconventional.

Originally Posted by franka

I would like to see the exact wording in the manual.

I can't attach the entire manual as the pdf is too big, but you can see it here:

http://www.bmwusa.com/Standard/Content/Owner/dgh.aspx

On page 37 it states:

Originally Posted by 2007 BMW X3 Owner's Manual

Do not allow the engine to warm up while parked; instead, start driving immediately at a moderate engine speed

That is pretty clear. Thanks

the most critical apsect of warmup is the oil temp. this is because oil viscosity changes with oil temp. When the oil is cool, it does not lubricate your engine properly(its too thick), especially if you run it hard. BMW's use of the oil temp guidelines will help your car last longer by preventing you from running your engine hard under substandard lubrication conditions. With an engine that has such close tolerances(any finely engineered powerplant), the oil must come up to a sufficient temperature so it is not too thick to lubricate properly. Kudos to BMW for using a better way to help you take care of your car. If you ignore their recommendations, the risk is higher engine wear and shorter engine life. If you live in temps near freezing, it can take 20 mins or more to warm up your engine to the optimal operating temperature needed to run it hard if left out overnight.

Originally Posted by desertdriver

the most critical apsect of warmup is the oil temp. this is because oil viscosity changes with oil temp. When the oil is cool, it does not lubricate your engine properly(its too thick), especially if you run it hard. BMW's use of the oil temp guidelines will help your car last longer by preventing you from running your engine hard under substandard lubrication conditions. With an engine that has such close tolerances(any finely engineered powerplant), the oil must come up to a sufficient temperature so it is not too thick to lubricate properly. Kudos to BMW for using a better way to help you take care of your car. If you ignore their recommendations, the risk is higher engine wear and shorter engine life. If you live in temps near freezing, it can take 20 mins or more to warm up your engine to the optimal operating temperature needed to run it hard if left out overnight.

All of that palaver might be true if it were actually "oil" we were talking about, but BMW engines are not lubricated with "oil". The lubricant is not especially viscous when cold. Moreover, cold engine parts are smaller than warm ones. As a result, there's no special thing about low operating temperatures that would inhibit lubrication of engine parts, and the engine will accept normal operating loads when cold without damage. The oil temperature gauge does not help with this because its cold peg is at 160 degrees -- the internal temperature of well-done meat. If the gauge serves any useful purpose, it is to flag high operating temperatures, which are detrimental to both the lubricant and the metal engine parts.

Originally Posted by raleedy

All of that palaver might be true if it were actually "oil" we were talking about, but BMW engines are not lubricated with "oil".

Help me out here. Jello? Peanut butter?

Originally Posted by raleedy

Moreover, cold engine parts are smaller than warm ones.

Please. You're talking about the molecular level.

desertdriver did not issue a 'palaver'; he was simply providing reasonable advice. No need to go 'high and mighty'.

Originally Posted by raleedy

All of that palaver might be true if it were actually "oil" we were talking about, but BMW engines are not lubricated with "oil". The lubricant is not especially viscous when cold. Moreover, cold engine parts are smaller than warm ones. As a result, there's no special thing about low operating temperatures that would inhibit lubrication of engine parts, and the engine will accept normal operating loads when cold without damage. The oil temperature gauge does not help with this because its cold peg is at 160 degrees -- the internal temperature of well-done meat. If the gauge serves any useful purpose, it is to flag high operating temperatures, which are detrimental to both the lubricant and the metal engine parts.

Dont confuse yourself with the synthetic vs petroleum oil arguements. Its all about hydrocarbon chain length and its relation to temperature dependent viscosity. All synthetic oils are hydrocarbons, just like petroleum based oils, they just have different polydispersity(better in synthetics). Think like a scientist not a lawyer. Molecular physics is molecualr physics, whether you pull the molecules out of the ground or synthesize them in a lab or plant the behaviors are consistent. the greater polydispersity of the mineral oils make them a bit better at lower temps.


Here is an article that compares the two if you care to read it. The (petroleum based)mineral oils actually lubricate better at low temps(thicker film before parts expand). this means that its even more important for synthetics to warm them up. Yeah, I used to be a metallurgist, so I know about expanding metals.

http://www.machinerylubrication.com/...?articleid=586

Originally Posted by raleedy

All of that palaver might be true if it were actually "oil" we were talking about, but BMW engines are not lubricated with "oil". The lubricant is not especially viscous when cold. Moreover, cold engine parts are smaller than warm ones. As a result, there's no special thing about low operating temperatures that would inhibit lubrication of engine parts, and the engine will accept normal operating loads when cold without damage. The oil temperature gauge does not help with this because its cold peg is at 160 degrees -- the internal temperature of well-done meat. If the gauge serves any useful purpose, it is to flag high operating temperatures, which are detrimental to both the lubricant and the metal engine parts.

Well then you should be very comfortable running WOT when cold, have at it.

Originally Posted by desertdriver

Dont confuse yourself with the synthetic vs petroleum oil arguements. Its all about hydrocarbon chain length and its relation to temperature dependent viscosity. All synthetic oils are hydrocarbons, just like petroleum based oils, they just have different polydispersity(better in synthetics). Think like a scientist not a lawyer. Molecular physics is molecualr physics, whether you pull the molecules out of the ground or synthesize them in a lab or plant the behaviors are consistent. the greater polydispersity of the mineral oils make them a bit better at lower temps.


Here is an article that compares the two if you care to read it. The (petroleum based)mineral oils actually lubricate better at low temps(thicker film before parts expand). this means that its even more important for synthetics to warm them up. Yeah, I used to be a metallurgist, so I know about expanding metals.

http://www.machinerylubrication.com/...?articleid=586

Just what I was going to say.

Originally Posted by LuvThatSam

Would that be for all vehicles?

I let my e46 get to just above the blue in the temp gauge, which is usually within a minute of starting.

Since the E46 and X3 are essentially the same (we also have a buffered coolant temp gauge), I suggest you do the same. I actually do this with all cars. I think its a reasonable time for the engine to settle, without letting it idle needlessly.