in another thread, it got slight OT w a discussion about whether to allow warmup before you drive

thought it might be good to hear other opinions

hopefully this doesnt go the way of oil discussions, politics, religon etc...just looking for what you do and the logic behind it

i operate with the idea of a short idle period...maybe 30 sec to a minute. before taking off in warmer weather to allow oil to get everywhere . in the colder months, i , when possible , let my cars idle a bit longer to allow the motor to get a bit of heat and expansion before taking off

i try to drive reaonable for a bit as well


in the case of my mini, it was a commuter car w 137k on it, so I have NO IDEA how it was treated..it burns no oil, seems solid motorwise, so it could have been that the owner either babied it OR drove it like a madman as soon as the key was hit

with new oil technology and metals/clearances as well as computer management systems, maybe the warmrup is not as big a need as in years past, when my cars had, YES , carbs... some of you younger guys can google what a carb is...haha

thoughts??

 

The advice I've heard is that modern cars do not require any warm up period, regardless of ambient temperature. The most efficient way to get the engine to peak operating temp is to drive 'gently' for the first few minutes, not to idle the engine. This may not apply if you live in an area with extremely cold temps, where you might need an engine block heater, for example. But for the vast majority of us motorers here in the states, idling is unnecessary, wasteful, and bad for the environment.

 

I edited this out of the other thread:


As far as the warm up thing, the old rule of thumb was to idle to temp. but that had more to do with natural lubricants and steel motors (parts did not expand as much), but with synthetic lubricants and alluminum motors (operating tollerances are spec.'d with the engines parts expanded @ operating temp.) it is recomended to get those parts to operating temps as soon as possible (within reason useing normal operating proceedures) with synthetic lubricants you don't get the wear associated with cold lubrucants that you did with the natural ones.

 

Oil has come a long way, but the physics of expanding metals at differant rates have not..
during mostly temperate//nonextreme conditions, hop in (let idle stablize, and oil presure build of course) and drive gently for a mile or two...
During those few days a year it it extreme (true subzero, not just below 32f), idleing for a minutes or two, then driving is fine imo.
Back in the day,folks would often let a car run at idle for 15+ min. to warm up...a bit excessive in a computer controled motor....things like carb icing, choking,etc are a thing of the past, and technology and operating principals have marched on.

 

I remember reading that 30 sec is all you need in very cold weather and not to abuse the engine (high revs) until the car has been running and rolling for at least a few minutes.

Also read that auto car starters that allow the car to idle and warm up can do harm to the engine

 

This is what I've heard too, and from very trusted sources. Idling the car, all you do is get the oil pan and engine block warm - and at -25° C, burn A LOT of gas - whereas it's just as important to get the gearbox and differential, wheel bearings, etc., warm. So you're better off giving it a minute or two tops, and then driving away slowly. I can't say as I've owned any car long enough to notice the long term effects of this type of warm-up, but as soon as I started doing it (in a 1992 Toyota Previa, last winter; I haven't owned my Mini for a Calgary winter yet), I noticed a significant - 20 or 30%?! - increase in fuel mileage (to no immediate detriment to the vehicle).

Certainly stomping on it before you're at operating temperature is still a no-no. Even at 40°C in the summer I won't open the throttle more than halfway, or shift above 3000 rpm or so, before getting the motor up to operating temperature.

 

My father in law (whole new forum needed, not just a new thread) would go to the garage, start his crown vic wagon, go back into the house and drink a cup of coffee. As S and G used to say, 'the man ain't got no culture'. Hit the starter, drive away gently and wait 'till the temp rises to normal then drive it like you stole it.

 

...And if millions more drivers were taught to drive away gently instead of sitting around warming up, there would be a lot less pollution.

Cars put out far more HC and CO when they're cold so you want to warm them up quickly. And by getting somewhere sooner instead of wasting gas, everyone would use less fuel and emit less greenhouse gases.

And so if everyone did stop idling so much then air quality would be better. Or at least it would get worse less fast. And then there would be less reason for stricter pollution regulations on cars. Which would mean they would build more fun cars.

(Unless smog is a mass hallucination and pollution controls are really an evil government conspiracy to destroy all fun and happiness everywhere, and then, uh, profit from that.)

 

Your probably right, but. I like keeping things in perspective.

And since I see about 2-3 R56/R55's a month all running no cats.....I doubt I could ever compensate for the CO/HC just one of those MINI's puts out in month even with a lifetime of my R53 doing a 30 second warm up......

Not to mention the fact that CHINA does'nt even use catalytic converters in their cars and they use about as much petrol as the USA.....

 

China doesn't have all that many cars. What they have is millions of two-stroke scooters. Which causes massive pollution in cities. Which is why in 2001 Shanghai banned normal gas scooters and made everyone use LPG fuel (propane) on their scooters. Which is a lot more harsh than just adding a catalytic converter.

In other words, China's doing the same thing as the US and Europe: they ignore the problem until it gets really bad, then they do something. When they have enough cars to make a significant contribution to their pollution problem, they'll do something.

Out of the 200,000+ Minis sold every year, I doubt more than a few percent ever have the catalytic converter removed. The public mostly wants mods that you can see from the outside of the car, like wheel spinners. And regardless of whether it's a lot or a few, or what China does or doesn't to, I can still do my little bit.