Do you guys warm up your X's??

[Krunk Man]

After driving my x5 hard and turning it off, the fan will kick in and help cool the x5 down after being shutoff.

[Scottie]

if I'm driving the X'er then I just jump in switch on and go

BUT

I can't do that in the winter on a frosty evening or morning I switch the car on and let the heater defrost windows .

I'm sure most folks would do the same with icey windows surely you just don't jump in the car and drive.

[cary]

Originally Posted by apetrov1x5

guys, i think it is more important not to switch the turbo-diesel engine off straight after we stop. i was told that many times and now i came to believe this. can anyone argue on that.

There is a time and reason to do this. The turbo gets very hot and runs at high speeds when you are running the car hard. If you are driving it hard and shut the engine off right away, the turbo can still be spinning and hot, with no oil being pumped through it. What then happens is you have no cooling occuring and oil temps in the turbo reaching 400+F.

In the old days, before synthetics were widely used, this would result in the oil cokeing and over time pluging the oil passages leading to inadequate oil flow and in the long term damaged bearings and shortened turbo life. It is less of a problem nowdays with water cooled turbos and synthetic oils, but it is still a good idea to idle down a turbo car for a minute or so if you are shutting it down after driving hard or immediately comming off the freeway. If you are just driving in town, there is no need to do this. If you are on the freeway get off and wait for the light to turn green, then pull in a parking lot and park, you really don't need to do it.

If you are running a lapping day at the track, when you pull off drive around gently for a few minutes and let it idle a few more minutes before shutting down (this also lets the other components cool, especially the brakes which can warp if you park when they are still hot).

As far as idling down normally aspirated cars, you don't need to do it. The only time you would ever want to, is if you are running them very hard and shut them down immediately (again track situation, also towing up a hill and then pulling over for that senic viewpoint). In those cases, let them idle down for a minute or two, you may even want to high idle them at 1500rpm or so. The reason for this is called heat soak. the engine has build up a lot of heat, you stop before it has dissapated and then you shut it down so the cooling system is holding hot fluid which then can boil over in local places (i.e. the heads) and cause the cooling system to boil over. Also, in some poorly designed motors, oil could pool in very hot places and potentially sludge.

[blackbeauty]

nope. too lazy to sit around and wait. i just zoom off as soon as i get in.

of course i look left and right first tho. LOL

[r6girl]

Originally Posted by cary

I'm going to chime in here since nobody has stated all the reasons you drive a car once it is started instead of letting it warm up. This applies to any car, not just BMW's.

1) An engine will have full oil pressure and lubercation to all the components within 20 seconds or so, and that is on the coldest morning starts.

2) Sitting and letting an engine warm up is prolonging the time the engine is running rich, which leads to fuel dilution of the oil, extra carbon buildup on the pistons and washdown of the lube on the cylinder walls from the excess gas.

3) Warming up the engine, only warms up the engine, but ignores the rest of the drivetrain that needs to also warm up, tranny, diffs, bearings in the wheels, transfer case.

4) An engine is not truly warmed up until the oil reaches operating temperature (200-220F). This takes about 10-15 minutes of normal driving. All the temp gauge shows is the coolant temp comming out of the engine which heats up and cools faster than the oil.

The best thing to do for any car is start it and drive away easily. No heavy throttle, no running it up to high RPMS. As it warms up you can take the RPMs higher and give it more throttle. If you want to go and really romp on it, give it 10 minutes or so of driving time to fully warm up.

great technical info - thanks, cary!

i let my X3 "warm up" only for as long as it takes me to put on my seatbelt and sunglasses, and turn on the radio. i keep the revs down until i've been driving for a few minutes (takes me about 5-7 minutes to get to the freeway on my way to work), and then i move into sport mode...

[X5Strap]

I always let it idle for a couple mins 1 or 2 and keep RPMs under 3000 until the engine is completly warmed up....temp gage in middle.

[WOOD56]

I surely don't.. at 105-110 Deg's. in Bahrain the gulf is hot. no need plus I have ....

[asawadude]

Similarly, Suby WRX's and cars equipped with aftermarket turbo-timers continue to run for a set time interval to allow the engines to cool down properly. There are benefits to a proper shutdown.

[at4689]

i just sit and go .

[DINANM3]

Originally Posted by Scottie

if I'm driving the X'er then I just jump in switch on and go

BUT

I can't do that in the winter on a frosty evening or morning I switch the car on and let the heater defrost windows .

I'm sure most folks would do the same with icey windows surely you just don't jump in the car and drive.

You ever heard of an ice scaper. IT takes way to long to wait till the defroster does its job imo